INTEGRATIONSNMBRSConnect Nmbrs to your other systems
Nmbrs, the Dutch payroll platform, calculates the salaries, but the data often comes from elsewhere: employees from the HR system, hours from planning. After the payroll run, the journal entries need to go to accounting. Connect all that and payroll retypes nothing, and the run matches the hours actually worked.
ISO 9001 & 27001
- Employees and employment contracts goes back and forth with Your other systems
- Hours, allowances and leave goes back and forth with Your other systems
- Journal entries goes back and forth with Your other systems
- Payroll run status goes back and forth with Your other systems
Built for clients including Tata Steel, M&G Investments, Digistore24, Toppers in Concert, Bar-le-Duc and Loogman
This is the data organisations most often let flow between systems. Which of it matters to you depends on where work is getting stuck today.
Employees and employment contracts
New starters, address changes, contracts and leavers. For integration builders, Nmbrs itself describes a basic scenario for synchronising employees and a more extensive HR scenario.
Hours, allowances and leave
Hours worked, allowances and leave from a planning or time-tracking system. Nmbrs has its own integration scenario for this too. The data has to land in the right payroll period.
Journal entries
After the payroll run, the payroll journal entries go to accounting, so finance doesn't have to post them by hand.
Payroll run status
When a run is finished or a journal has been created. Other systems can wait for this, for example to update labour costs per project or cost centre.
Departments, job titles and cost centres
The structure used to allocate labour costs. If it's the same in Nmbrs, the HR system and accounting, your reports line up.
For each combination: which data moves back and forth, what the standard integration does and what to watch out for.
Not always. If an existing integration for Nmbrs does exactly what you need, we'll tell you.
The Nmbrs App Store lists the standardised integrations with Nmbrs. For accounting, there are integrations that send journal entries directly. The integration with Exact Online is built and maintained by Exact Online itself. You activate it from Nmbrs, and the journal entries are split by period and by cost centre or cost type.
Such an integration is enough if you only want to send journal entries to accounting, or if your HR package has an integration in the App Store that covers exactly the fields you use. Nmbrs itself says that not every integration suits every employer, and that you may use the API for your own private integration.
- Your integration still runs on the SOAP API and has to move to REST before 1 March 2027.
- Hours and allowances from your own planning tool need to arrive as pay components in the right period.
- You run payroll for many employers and want to manage consent and errors per employer clearly.
- Labour costs per project or cost centre need to go back to a system other than accounting.
REST API with OAuth 2.0
The REST API, version 1.0, is the newest Nmbrs API. Authentication uses the OAuth 2.0 Authorization Code Flow: the Nmbrs user grants consent for what your integration asks. You register your app in the developer portal and receive a client ID and secret. You also send a subscription key with every request.
Consent per employer
Logging in through the REST API only works at debtor level, not with a master login in an Nmbrs accountant environment. For an accountancy firm with many employers, that means arranging and tracking consent for each employer.
SOAP ends on 1 March 2027
Older integrations use the SOAP API, version 3.0, with a username and API token. Nmbrs ends support for it on 1 March 2027 and recommends the REST API. If your integration still runs on SOAP, plan the move well before that date.
Limits and testing
How many requests you can make depends on the subscription you choose in the developer portal. During development, that number is lower. Nmbrs only approves a production subscription with higher limits after a successful demo. To test, you need an Nmbrs test account.
Webhooks and periods
You set up webhooks at debtor level, for example for a completed run or a created journal, and you can also manage them through the API. Keep in mind that Nmbrs works in periods: January is period 1, and an employer runs payroll monthly, four-weekly or weekly.
An integration moves data. In between, AI can read, sort and prepare a suggestion. Where it matters, a person decides.
Spotting anomalies before the run
AI can compare hours and allowances with the roster and with previous periods, and flag lines that stand out: a doubling, an allowance without an evening shift. The payroll administrator reviews them and decides. The payroll run itself stays human work.
Explanations without salary data
An assistant can explain to employees what a pay component means, based on your own explanations and the collective labour agreement (cao). It doesn't need access to individual payslips for that. Questions about someone's own salary go to a person.
What AI doesn't see
Salary data and BSN numbers don't belong in a prompt. If you do connect an AI step to Nmbrs, give it only the data it needs, log every call and don't let it change anything.
Changes in the wrong period
A change that lands in the wrong period leads to a correction in a later run. Decide beforehand, per data flow, which date determines the period: the work date, the approval date or the effective date.
The weekly update
Nmbrs schedules an update every week, usually on Wednesday at 8pm. A batch running at that moment can fail. Check the status page and schedule large synchronisations at another time.
Two sources for one employee
If you run an HR system alongside Nmbrs, decide which system leads for address, contract and bank account. Otherwise they overwrite each other and nobody knows which value is right.
One employer goes quiet
Because you get consent per employer, the integration can stop for one employer while the rest keeps running. So monitor per employer, not just the integration as a whole.
What goes where
Which data moves, in which direction, and which system wins when two values differ. That is written down before anything gets built. For this integration, that means: Employees and employment contracts, Hours, allowances and leave, Journal entries, Payroll run status, Departments, job titles and cost centres.
Fields and rules
For every field, how it translates between the systems: statuses, VAT codes, general ledger accounts, item numbers. And what happens with a duplicate or a missing value. For this integration, that means: REST API with OAuth 2.0, Consent per employer, SOAP ends on 1 March 2027, Limits and testing, Webhooks and periods.
Testing with real cases
In a sandbox or test administration, with the exceptions you actually run into: credit notes, partial deliveries, changed customer details.
Live, with logging and monitoring
Every sync is logged, and when something fails, someone gets an alert. If a vendor changes its API, we update the integration.
No account manager. You talk to someone who builds integrations themselves, and who will tell you when a standard integration is enough.
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Does Nmbrs have an API?
Yes. Nmbrs has a REST API, version 1.0, with OAuth 2.0, and an older SOAP API, version 3.0. For the REST API you sign up in the developer portal, register your app and take out a subscription that gives you a subscription key.
What is happening to the Nmbrs SOAP API?
Nmbrs ends support for the SOAP API on 1 March 2027 and recommends moving to the REST API. Integrations that still use SOAP need to be rebuilt before that date. Note: with REST, authorisation is per employer, not through a master login.
Does Nmbrs have webhooks?
Yes. You set them up at debtor level, under Integrations, with a name, an endpoint and the actions you want to be notified about, such as a completed run or a created journal. After the notification, you fetch the details through the API.
Can Nmbrs send journal entries to accounting automatically?
Yes, for a number of accounting packages. The integration with Exact Online is built and maintained by Exact Online, and you activate it from Nmbrs. The journal entries are then split by period and by cost centre or cost type.
How do I test an integration with Nmbrs?
You need an Nmbrs test account and a development subscription in the developer portal. Lower limits apply than in production. Nmbrs only approves the production subscription after a successful demo, so build that into your planning.
Can AI access salary data in Nmbrs?
Be cautious. Salary data and BSN numbers are sensitive personal data under the GDPR. Let AI work with data from before the payroll run, such as hours and rosters, or with general explanations, and don't give it write access in Nmbrs.
Sources
The technical facts on this page come from the vendors' official documentation, checked on 19 September 2026. Vendors change their APIs and limits; when we build an integration, we always check the current state.