Does your ISS calculation match your service invoices, period by period?
Checking ISS (Brazil's municipal service tax) only against the monthly total can hide differences between tax periods. The proof has three sides: the tax period, the payment slip and the service invoice, with every invoice left out explained.
Each municipality sets its own rules, and the tax decision is your company's. DFSpro designs, configures and proves the path from the number back to the invoice.
Start with the question your role needs to answer
Four entry points to the same proof: each role sees a different part of the ISS calculation.
01Tax and legal
What the complementary law sets, what belongs to the municipality, withholding, and the list of invoices left out of the return.
See this role's section02Accounting
From the calculated tax to the payment slip and the ledger: three balances that must agree, and what to do when they do not.
See this role's section03Audit and internal control
The proof report, the evidence package and the controls behind every close.
See this role's section04IT and master data
The key that links the invoice to the tax, the rules table by municipality, and the scenarios the test must cover.
See this role's sectionISS proof shortcuts
A proof that goes from the total down to the invoice
Proving ISS means showing that, in each tax period, the base and the tax calculated match the service invoices the company considers eligible.
What is compared
The base and tax of the calculation against the invoices of the period, the payment slip against the tax owed, and the ledger balance against both.
At what level
By tax period, by municipality and by invoice. The total for the period is only a starting point, never the proof.
What is kept
The list of invoices left out of the return, with the reason for each, and the company's decision where the rule left room.
The tax calculation shows how much is owed. The NFS-e (Brazil's electronic service invoice) handles issuing and withholding on the invoice. The proof links the two: it is what the company shows when someone asks where the number came from.
Six places where the total hides the difference
The monthly total is the first check. These are the reasons it is not enough.
Two errors that cancel out
One invoice booked too high in a period and another booked too low in the same period give a correct total and two wrong periods. The total closes and the proof fails.
Tax period is not payment
The invoice belongs to one month, and the payment slip may be paid in another. Each municipality sets its own rule for tax period and due date, and the proof shows both dates side by side, without assuming they match.
Municipality is not a detail
ISS is a tax of the municipalities and the Federal District. A total that mixes municipalities mixes rates, withholding rules and payment slips, and a check by total separates none of that.
Withheld is not own
Part of the ISS shown on the invoice was withheld by the service recipient, and part is owed by the provider itself. Mixing the two balances makes the payment slip look right and the ledger look wrong.
Left out is not forgotten
Some invoices stay out of the return for a legitimate reason. Without a list with the reason, the company cannot tell a correct exclusion from an error nobody saw.
Cancellation arrives late
Cancelling or replacing an invoice after the payment slip was paid changes the original tax period. The proof must show what changed and in which period the effect was handled.
The total for the period works as an alarm. If it does not close, there is a difference. If it closes, tax period, municipality, withholding and payment slip still need proof. The check ends only when every invoice has a place in the calculation.
Tax period, payment slip and invoice, linked to each other
Each side answers a different question. Only the three together close the check.
Tax period side
Question: do the base and tax calculated in each tax period match the eligible invoices of that period? Proof: the list of invoices by tax period, linked to the total of the calculation.
Payment slip side
Question: does each payment slip link to a set of invoices, and does the amount paid match the tax owed? Proof: the link between payment slip, tax period and invoices, with the payment confirmed.
Invoice side
Question: does each invoice have the right base, rate, municipality and withholding, and was it handled in the right place? Proof: the trail from the invoice to the tax, the posting and the payment slip.
The path the proof follows
- 01
Service invoice
The invoice issued or received, with municipality, service code, base, rate, withholding and status.
- 02
Calculation for the period
The own tax, the withheld tax and the balance, by municipality and by tax period.
- 03
Payment slip and payment
The amount paid, the tax period it refers to and the date the municipality received it.
- 04
Accounting entry
The tax payable, the tax withheld and the matching expense or credit, each in its own account.
- 05
Return to the municipality
What was reported to the municipality, when the local rule asks for its own return.
- 06
Proof report
The comparison of the five steps, with the difference, the cause and the owner of each point that does not close.
The proof walks this path in both directions: from the invoice to the payment, to show that nothing was left without tax, and from the payment to the invoice, to show that the payment slip does not pay what the invoice does not justify.
Seven rules of Complementary Law 116 and what the proof does with each one
The complementary law sets what applies to all municipalities. The check starts from it and adds the local rule on top.
| Rule | What Complementary Law 116/2003 says | What the proof does with it |
|---|---|---|
| Taxable event (art. 1) | The provision of services on the attached list, even if it is not the provider's main activity. Taxation does not depend on the name given to the service. | Checks that each invoiced service has a code on the list and that the code on the invoice matches the service actually provided. |
| Service and goods (art. 1, § 2) | Except for the exceptions on the list, the services it covers are not subject to ICMS (Brazil's state value-added tax), even if they involve supplying goods. | On a mixed invoice, separates what the list treats as service from what follows another rule, before adding up the base. |
| Export (art. 2) | The tax does not apply to the export of services. A service developed in Brazil whose result is verified here is not an export, even if payment comes from abroad. | Keeps the export invoice on the list of invoices outside the base, with the reason written down. |
| Taxpayer and place (arts. 3 to 5) | The taxpayer is the provider. As a rule the tax is owed at the provider's establishment, with exceptions by type of service where the place is another. | Groups the calculation by the municipality where the tax is owed, not only by the municipality of issue. |
| Responsibility (art. 6) | Municipalities may assign by law responsibility to a third party linked to the taxable event. The responsible party answers for the full payment, even if it did not withhold. | Separates the company's own tax from the tax it owes as the responsible party, on both ends of the transaction. |
| Tax base (art. 7) | The base is the price of the service. In services under items 7.02 and 7.05, the value of materials supplied by the provider is not part of the base. | Compares the base on the invoice with the price of the service and checks where the law provides an exclusion. |
| Rates (arts. 8 and 8-A) | The maximum rate is 5% and the minimum is 2%. The law forbids any benefit that results in a burden below the minimum, except for items 7.02, 7.05 and 16.01. | Checks the rate on each invoice against the municipality's law on the date of the service, within those limits. |
Federal law defines the common design. The exact rate, the deadline, how to file, withholding and what counts as the tax period come from the law of each municipality and of the Federal District, and the proof uses both layers. The national NFS-e standard makes the invoice uniform, and the tax stays municipal.
Complementary Law 116/2003, arts. 1 to 8-A, in the consolidated text published by Planalto, with the changes made by Complementary Laws 157/2016, 175/2020, 183/2021, 214/2025 and 218/2025.
The place of taxation changes the math for each municipality
The same service may be taxed in a different municipality from the one that issued the invoice. The check needs to know which rule applies to each type of service.
General rule
The starting point is the provider's establishment or, without an establishment, the provider's home. Art. 4 defines an establishment as the place where the activity is carried out, permanently or temporarily, as an economic or professional unit.
Construction and work on site
For services such as construction, demolition, street cleaning, gardening and shoring, the tax is owed where the service is carried out. Art. 3 lists each item.
Service recipient's home
From 2016 and from 2020, some activities began to follow the recipient's home, such as health plans and medicine, card, consortium and fund administration, and leasing.
Service from abroad
The tax also applies to a service coming from abroad or whose provision began outside the country (art. 1, § 1). In that case the recipient or the intermediary is the responsible party (art. 6, § 2).
Transport, roads and pipelines
For transport, the tax is owed in the municipality where it is carried out. For highway operation, in each municipality with a stretch of highway. For pipelines, cables and poles under item 3.04, in each municipality they cross, and the base is proportional (art. 7, § 1).
Minimum rate and place
If a municipality does not respect the 2% minimum rate on a service provided to a recipient in another municipality, the law or act is void and the provider has the right to a refund of what it paid (art. 8-A, §§ 2 and 3).
The effect on the proof is direct: if the invoice says the service was provided in one municipality and the law says to tax it in another, a calculation by municipality of issue is right in total and wrong in distribution. The rules table by municipality shows where this happens in your case.
Complementary Law 116/2003, arts. 1, 3, 4, 6 and 8-A. The changes to art. 3 come from Complementary Laws 157/2016, 175/2020 and 218/2025.
What federal law limits and what belongs to the municipality
The complementary law sets the base and the rate range. The exact rule by service and by date is local.
Price of the service
Art. 7 defines the base as the price of the service. The proof compares the base on the invoice with the invoiced amount and explains every difference, such as a discount, materials or a deduction provided by municipal law.
Materials on construction work
Under items 7.02 and 7.05, the value of materials supplied by the provider is not part of the base (art. 7, § 2, I). Whoever provides these services needs to separate materials and service on the invoice to prove the base.
5% ceiling
The complementary law sets the maximum rate at 5% (art. 8). A rate above that, on the invoice or in the master data, is a sign of a setup error before it is a question of legal thesis.
2% floor
The minimum rate is 2% (art. 8-A), and the law forbids an incentive that takes the burden below that, except under items 7.02, 7.05 and 16.01. The proof must identify where the local rule falls below the floor and what the company decided to do.
The check by invoice uses a table of rates by municipality, by service code and by validity period. Without the validity period, the rate of the previous tax period contaminates the next one, and the error shows up only in the return.
A company with a rates table that has a start and end date for each rule can redo an old tax period with the rate that applied at the time. A company with only the current rate cannot.
Own tax, withheld by you, and withheld from you
Withholding creates two sides and three balances. Mixing them is the road to a payment slip that looks right and a ledger that does not close.
Own ISS
What the company owes as a provider, under the rule of the municipality where the tax is owed. It is the balance the company's payment slip settles.
ISS withheld by you
What the company withheld when buying services from third parties, when the municipality's law makes it responsible. It is a balance payable that does not belong to the own tax.
ISS withheld from you
What customers withheld from the company. It reduces what the company pays as a provider and needs proof of withholding, so it does not turn into a difference at the end of the period.
Who is responsible comes from the municipality's law, within art. 6: a third party linked to the taxable event, a recipient of services from abroad, and a legal entity that receives services under certain items of the list. Each municipality needs a row in the rules table saying whether there is withholding and in which cases.
Art. 6, § 1, says the responsible parties must pay the full tax, the fine and the additions, whether or not the withholding was made. So the proof for whoever withholds does not end at the invoice: it ends at the payment slip and the ledger.
Issuing and receiving an invoice with withholding are covered in national-standard NFS-e and in service invoice automation.
The list with reasons is part of the proof
Every invoice issued or received that did not enter the return needs a written explanation. These are the reasons and what each one rests on.
| Reason | Where it comes from | What the list records |
|---|---|---|
| Export of services | LC 116, art. 2, I. The sole paragraph excludes from this rule a service done in Brazil with the result here, even if paid from abroad. | The invoice, where the result goes and the customer's decision on the classification. |
| Outside the scope of the tax | LC 116, art. 2, II and III: employment relationships, independent workers, directors and board members, and amounts from financial intermediation and credit operations of financial institutions. | The type of operation and the legal basis. |
| Taxed in another municipality | LC 116, art. 3: the tax is owed where the law says, which may not be the municipality of the invoice. | The invoice, the municipality of taxation and the calculation it entered. |
| Goods, not service | LC 116, art. 1, § 2, and the attached list: what is not a service on the list follows another rule. | The goods part of the invoice and the tax that applies to it. |
| Cancelled or replaced invoice | Each municipality's rule on cancellation and replacement. | The original invoice, the new invoice and the tax period in which the effect was handled. |
| Tax withheld by a third party | LC 116, art. 6: the invoice enters the calculation and the tax is paid by the responsible party. | The proof of withholding and the balance that no longer goes to the company's payment slip. |
| Invoice with no final status yet | The rule for authorizing and confirming the invoice at the municipality. | The reason for the pending item, the owner and the expected date of handling. |
Each row of the list has an invoice, a reason, a legal basis or municipal rule, an owner and a status. The decision on how to classify an invoice is the company's. DFSpro keeps the list, the evidence and the history of who decided.
What the national environment improves in the proof and what stays local
The invoice now has a common layout. Each municipality's rule does not.
What becomes national
Complementary Law 214/2025 requires municipalities and the Federal District, from 01/01/2026 until 31/12/2032, to authorize the national-standard NFS-e or to share with the national environment the documents of their own issuing system (art. 62, § 1 and § 2).
What stays municipal
The tax, the rate, withholding and the deadline follow each municipality's law. The standard defines the layout of the invoice, not the taxation rule.
The national environment stores the invoice in the same layout, which helps the proof. The company still needs to link each invoice to the tax, the payment slip and the ledger in its own system. Issuing, events and withholding on the invoice are covered in national-standard NFS-e.
One row per municipality, with source and validity period
Each municipality's rule does not need to become a separate case. It becomes a row in a single table, with an official source and an owner.
| Table column | What it records | Why the table needs it |
|---|---|---|
| Municipality and validity | Municipality, start date and end date of the rule. | The rule changes over time, and the proof for an old tax period uses the rule of that date. |
| Official source | Law, decree or instruction, with a link to the text in force. | An auditor asks where the rule came from. The answer is a document, not a memory. |
| Rates by service | Rate by service code, with the law that sets it. | The check by invoice uses this column as the expected value. |
| Withholding | Whether there is withholding, who withholds and for which services. | Defines the own and withheld balances, and what the company withholds as a recipient. |
| Tax period and due date | How the municipality defines the tax period and when the payment slip is due. | Links the invoice to the right month and the payment slip to the right deadline. |
| Return | Whether the municipality requires its own return, by what deadline and in what format. | The proof includes what was reported to the municipality, when the rule asks for it. |
| Cancellation and replacement | Deadline and procedure to cancel or replace an invoice. | Defines the tax period in which a late cancellation is handled. |
| Benefits and special regimes | Benefit, regime or reduced base, with the law that grants it. | Each benefit must stay within the limits of the complementary law, and the decision to use it is the customer's. |
| Review owner | Who in the company confirms the rule, and the date of the last review. | A rule with no owner ages without anyone noticing. |
The table has one row per municipality and per validity period. It is the only source of municipal rules that the calculation and the test use.
Until 2032, ISS proof coexists with IBS and CBS
ISS does not disappear all at once. It shrinks year by year and ceases to exist in 2033. Each year has a different rate rule.
Until 2032 there is ISS to calculate and prove. Each year, what changes is the rate, the benefit and the coexistence with IBS (the state and city consumption tax created by the reform) and CBS (the federal consumption tax created by the reform) on the same invoice.
Timeline of ISS in the transition
- 01
Today
ISS follows Complementary Law 116 and each municipality's law, with rates between 2% and 5%.
- 02
2027 and 2028
IBS is charged at a 0.05% state rate and a 0.05% municipal rate, and CBS is reduced by 0.1 percentage point (EC 132, ADCT, art. 127).
- 03
2029 to 2032
ISS rates fall gradually: 10% in 2029, 20% in 2030, 30% in 2031 and 40% in 2032, on the rates in force on 31/12/2028, and the benefits fall in the same proportion (LC 116, art. 8-B).
- 04
2033
ISS is abolished from 2033 (EC 132, ADCT, art. 129).
What to do with this in the check
Rates table with validity period
Each year from 2029 to 2032 has a different effective rate for the same service. The table by municipality needs to record the rate set by law and the reduction percentage for the year.
Benefit reduced in the same proportion
Whoever has a municipal benefit needs to check how it is reduced each year. Art. 8-B deals with benefits already reduced because of the rate reduction, and the reading of each case is the customer's.
Invoice with more than one tax
Art. 62 of Complementary Law 214 requires the invoice authorization systems to adapt to a layout that allows reporting IBS and CBS. The check starts to separate, on the same invoice, what is ISS from what is the new tax.
How much to prepare and when is the customer's decision. What DFSpro delivers is the table by validity period, the report with its own column for the new tax, and the proof that the two coexist without contaminating each other's balance. See also the page on tax reform with CBS and IBS.
Constitutional Amendment 132/2023, arts. 127 to 129 of the ADCT; Complementary Law 116/2003, art. 8-B, added by Complementary Law 214/2025; Complementary Law 214/2025, art. 62.
The core piece: a list with key, cause and owner
This is what DFSpro designs with the company. Without it, the check depends on spreadsheets that change every month.
| Report field | What it holds | What it is for |
|---|---|---|
| Invoice key | Municipality, number, series or verification code, tax period and status. | Links the invoice to the tax without a manual spreadsheet. |
| Municipality of taxation | The municipality where the tax is owed, under the law's place rule. | Groups the calculation where the payment slip is paid. |
| Service code and rate | The code from the list and the rate applied, with the rule that sets it. | Compares the rate on the invoice with the expected value in the table. |
| Invoice base and tax | The price of the service, the exclusions and the tax calculated. | Closes the tax period by the sum of the invoices. |
| Withholding | Whether the tax was withheld, by whom and in what amount. | Separates the own balance from the withheld balance. |
| Payment slip | Number, tax period, amount paid and payment date. | Links the invoice to the payment. |
| Ledger | The account, the entry and the accounting value of the tax. | Closes the third side of the proof. |
| Difference and cause | The amount over or under and the classified cause. | Separates what is expected from what is an error. |
| Owner and status | Who corrects or decides, and whether the difference is open, explained or accepted by the customer. | Avoids the difference nobody owns. |
| Evidence | The document, screen or file that supports the cause and the fix. | Leaves the proof ready for whoever audits. |
From the total to the invoice, in four steps down
- 01
Total for the period
Compare the tax calculated with the tax booked, by tax type and by establishment.
- 02
Tax period and municipality
Where the total does not close, go down to the tax period and the municipality that hold the difference.
- 03
Invoice
Open the list of invoices for the municipality and the tax period and look for what exists on one side and is missing on the other.
- 04
Cause and owner
Classify each finding under one of the causes in the report and hand it to the owner, with the evidence.
Three design decisions weigh more than the rest: which key links the invoice to the entry, at what level the comparison is made, and who can change the status of a difference. The report must run again at every close, with the same criteria, so that comparing months makes sense.
Eight scenarios the proof test must cover
The ISS proof can be trusted only if the system gets the hard cases right. These are the ones that weigh most.
Service taxed in another municipality
An invoice issued in one municipality for a service whose rule says to tax it in another. The test checks which calculation the invoice entered.
Withholding by the recipient
An invoice with withholding to be paid by the recipient company. The test checks the withheld balance, the accounting account and the responsible party's payment slip.
Withholding suffered by the provider
An invoice issued with withholding by the customer. The test checks the reduction of the own tax and the proof of withholding.
Cancellation after the payment slip
An invoice cancelled after payment. The test checks the tax period in which the effect is handled and the impact on the balance.
Invoice replacement
An invoice replaced by another. The test checks that only the new one enters the calculation and that the old one stays on the list with the reason.
Rate change during the month
A rate that changes validity in the middle of the month. The test checks that each invoice uses the rate of its own date.
Export of services
A service provided abroad with the result outside the country. The test checks that the invoice stays out of the base with the reason recorded.
Service received from abroad
A service hired from a resident abroad. The test checks the tax to be paid by the recipient and the matching entry.
The eight scenarios are the minimum. Each company adds its own, and tax testing proves each one with expected values written down before the run, instead of reading the result afterward.
Eight errors that push the difference to the next period
Each error has a cause and a way out.
| Error | Why it happens | How to avoid it |
|---|---|---|
| Checking only the monthly total | The total closes because two errors offset each other. | Go down to the tax period, the municipality and the invoice whenever the total is the only proof. |
| Mixing tax period and payment | The payment slip is paid in another month and the reconciliation links it to the wrong tax period. | Record both dates and link the payment slip to the tax period it refers to. |
| Rate without validity period | The table keeps only the current rate, and the previous month is recalculated with it. | A table by municipality, service and validity period, with the law that sets each rule. |
| Withheld balance in the own balance | The tax payable account receives the own and the withheld tax without separation. | Separate accounts and report lines for own tax and withheld tax. |
| Municipality of issue as municipality of taxation | The system groups by the invoice's municipality, and the law says to tax in another. | A municipality of taxation field on the invoice, calculated by the place rule. |
| Cancellation with no trace | The invoice disappears from the calculation and nobody records the effect on the tax period already paid. | A list of cancelled and replaced invoices, with the tax period of handling. |
| Export with no written reason | The invoice stays out of the base and nobody can say why. | A list of invoices left out of the return, with reason and legal basis. |
| Municipal rule in a loose file | The rule lives in a personal spreadsheet and is lost when the person changes. | A single table by municipality, with an official source and a review owner. |
The pattern repeats: the error lives in the handoff between two areas or two systems. The effect of this on the month-end close is covered in unstable tax close.
Six controls the company keeps between one close and the next
A month's evidence holds up only if these controls exist in the previous month and in the next one.
ISS close calendar
Who closes what and in what order, with the date of each check and the point where the tax period is locked against changes.
Rules table by municipality
The table with source, validity period and review owner, updated when a municipality changes a rule.
List of invoices left out of the return
Each invoice left out, with reason and owner, reviewed at every close.
List of cancellations and replacements
The invoices changed after the close, with the tax period in which the effect was handled.
Balances that cross periods
The withheld tax payable, the tax to recover and the balance of the previous tax period, each with its account.
Access and segregation
Who changes the setup, posts to the ledger and approves the close, with the change history of the report.
The package someone else can open months later
Seven items make up the package.
| Package item | What it keeps | Who it serves |
|---|---|---|
| Proof report for the tax period | The final version, with issue date and the criteria used. | Audit and internal control |
| Payment slip and proof of payment | The payment slip for each municipality, with the amount and payment date. | Tax and accounting |
| Return filed with the municipality | The file or receipt, when the local rule requires a return. | Tax |
| List of invoices left out | The list with reason, legal basis and the customer's decision. | Audit and legal |
| Rules table in force | The version of the table used for the tax period, with the sources. | Tax and IT |
| Customer decisions | The record of each difference accepted or each classification adopted, with the date and the name of who decided. | Audit and legal |
| Items carried to the next month | The list of what stayed open, with owner and deadline. | All areas |
Close proof is a set of files and decisions, not a conversation. Align how long the package is kept with the period the company's accountant and legal team indicate for each municipality.
Four areas, four responsibilities in the proof
A difference with no owner crosses the month and comes back in the next. Each area answers for the cause it can correct.
Tax
Defines the rule for each municipality, validates the rules table and decides how to classify the invoices left out of the return.
Accounting
Checks the balance payable in the ledger, separates own tax from withheld tax and records the correction entries.
IT and master data
Keeps the service master data, the rates table and the proof report running at every close.
Internal control and audit
Receives the proof report and the evidence package, and checks that the controls exist.
The four areas answer for different causes of difference. The tax master data and the setup are where the proof depends on IT, and the municipal rule is where it depends on tax.
From the ISS map to the first close proven
Six deliveries, in order. The proof report is the center, and the others support it.
- 01
ISS map
A survey of where the tax arises in your environment: municipalities, types of service, invoices issued and received, withholdings and payment slips.
- 02
Rules table
Building the table by municipality, with official source, validity period and review owner.
- 03
Proof report
Design and build of the report, with the key, cause and owner of each difference.
- 04
Test scenarios
Writing the scenarios and the expected values, and proving that the system gets each one right.
- 05
Evidence trail
The close package, with payment slips, decisions, the list of invoices left out and corrections, ready for audit.
- 06
First close
Support for the first tax period with the report in use, until the difference falls to a level the company accepts.
The work starts with the SAP Tax Diagnostic or with the first close after a migration to S/4HANA.
In a rollout to a new unit, the report goes in before the first tax period. In ongoing support, it runs every tax period within AMS Fiscal.
The report is the same with or without GUEPARDO Tax. The product belongs to NTT DATA, and DFSpro is an Authorized Channel: it sells the license, implements it and runs the governance. Where the environment uses the product, the design starts from what it covers, and what it does not cover is recorded in the rules table.
Who proves and who decides
The check shows what the system does. What to do with a difference is the decision of whoever answers for the company.
DFSpro designs the proof report, configures the evidence trail and proves, with the data from your environment, that the system delivers the result the company defined. Each municipality's rule and the tax decision are your company's.
DFSpro proves
- Where each difference arises and from what cause.
- That the fix made in the system produces the agreed value.
- That the report and the evidence repeat at every close.
The company decides
- The rule that applies to each municipality and the classification of each service.
- The treatment of withholding, of benefits and of any tax thesis.
- Whether a difference is acceptable or must be corrected.
- The approval of the close and the position toward the municipality.
DFSpro's full role in any tax work is described in how we work with your team.
Standards and reference pages
The federal rules come from these documents. Each municipality's rule is in that municipality's own law.
Frequently asked questions about ISS calculation
Understanding the proof4 questions, 01 to 04
01What does it mean to prove the ISS calculation by tax period?
Checking, in each tax period, that the base and tax calculated match the service invoices the company considers eligible. The total for the period can close while two tax periods are wrong in opposite directions. What is eligible depends on the municipality's rule and the company's decision.
02Why may the tax period of the invoice and of the payment not match?
Because each municipality sets its own rule for tax period and due date, and the invoice may belong to one month while the payment slip is paid in another. The proof records the tax period of each invoice and the date of each payment, without assuming they are the same.
03What is the difference between the payment slip and the services return for whoever does the check?
The payment slip is the payment, and the return is the information filed with the municipality. Each may have its own rule, deadline and content, set by local law. The proof links the invoices to the return and the payment slip, and explains any difference between them.
04What can the municipality ask for to prove the ISS paid?
It depends on each municipality. In general, the company needs to show the invoices, the payment slip and the return for each tax period, linked to each other. Keeping this trail reduces the effort of answering, and what will be required is checked in the local rule.
Each municipality's rule4 questions, 05 to 08
05How do you organize each municipality's rule without creating a separate case for each one?
By gathering the rules in a single table, with one row per municipality and per validity period, with the official source and the review owner. The rule stops living in personal spreadsheets. DFSpro helps structure the table, and the content comes from the municipality's law.
06What should be done with service invoices left out of the return?
Keep a list of these invoices with the reason for each exclusion, so the company can explain why they did not enter. The criteria for what goes in and what stays out come from the municipality's rule and the company's decision. The list is part of the proof.
07How do you separate, in the proof, the ISS the company owes from what was withheld by third parties?
Withholding creates two sides: who withholds and who suffers the withholding. The proof shows, for each tax period, what is own tax and what was withheld, without mixing the balances. Who can be responsible is defined by the municipality's law, within art. 6 of Complementary Law 116.
08Is the tax always owed in the municipality that issued the invoice?
No. The general rule in Complementary Law 116 is the provider's establishment, but art. 3 brings exceptions by type of service, where the tax is owed where the service is carried out or at the recipient's home. The check groups the calculation by municipality of taxation.
Hiring and getting started4 questions, 09 to 12
09What information should be gathered before asking for a review of the ISS calculation?
In which municipalities there is ISS on services provided and received, whether the check today is by tax period or by payment slip, whether there are invoices with withholding, and which return is filed. With these answers the scope conversation stays focused. Price and timing are handled in direct contact.
10Is the ISS check a job for tax, accounting or IT?
All three, in different roles. Tax defines the rule and validates the result, accounting checks the balance payable, and IT makes sure the environment supports the design. DFSpro steps in designing, configuring and proving, and the tax decision remains the company's.
11Does DFSpro define the rate or the classification of my service?
No. The rate, the classification and any tax treatment are decisions of the company, with its accountants and lawyers, within the municipality's law. DFSpro records the chosen rule in the table, configures the system to apply it and proves that each invoice follows what the company decided.
12Can we start with just one municipality?
Yes. The initial scope is defined together and can prove the method. It does not count as proof for the other municipalities, because each has its own rule. What is left out must be written down, with an owner and a review date.
Reform and decision2 questions, 13 to 14
13Does the tax reform change how ISS is proven?
It changes gradually. From 2029 to 2032 ISS rates are reduced by 10%, 20%, 30% and 40% of the rates in force on 31/12/2028, and the tax is abolished from 2033. Until then, proof by tax period, by payment slip and by invoice remains necessary, with a rates table by validity period.
14How do you know if the current ISS check depends too much on one person?
If only one person knows each municipality's rule, if nobody can redo a closed tax period without that person, or if the audit asks for a trail that the current control does not give. It is a risk criterion, without a number, and the decision to change is the company's.
Bring the latest tax period and the list of what did not match
Describe the ISS difference that repeats most in your close. The conversation covers your municipalities, the invoices issued and received, and who decides each point, with no price and no commitment on timing.
To read more first: unstable tax close and gap between tax and IT.