Skip to main content
In Canada, employers may be required to contribute to a Workers’ Compensation Board (WCB), which funds insurance for employees in case of work-related injuries or illnesses. Premiums are calculated based on the employer’s industry classification and total payroll. The Nmbr API supports WCB premium estimation for every province and territory. To enable WCB calculations, a WCB tax-property must be configured per province.

​
Supported Regions

WCB premiums are supported for all Canadian jurisdictions, including:

​
Enabling WCB Calculation

To calculate WCB premiums in any province or territory, you must define a WCB tax-property for each work-assignment using the tax_properties API. Each region uses the format ca::<region_code>::workers_compensation_class as the type value. For example:
  • Ontario: ca::on::workers_compensation_class
  • Quebec: ca::qc::workers_compensation_class
  • Yukon: ca::yt::workers_compensation_class
The value object for the tax-property must include:
  • rate (number, required) – The WCB premium rate to apply (e.g., 1.85).
  • code (string, required) – The business’s WCB classification or rate group code.
  • industry (string, required) – A plain-text label describing the business activity or industry.
  • historical_remuneration (number, optional) – Year-to-date insurable earnings for the work-assignment, used to reduce premiums at the annual provincial maximum.

"value": {
  "rate": 1.85,
  "code": "83202",
  "industry": "Technology consulting",
  "historical_remuneration": 740000
}
WCB will not be calculated for any work-assignment unless a valid tax-property is configured for its province of employment.

​
Provincial Maximums

Nmbr automatically applies the maximum assessable earnings for each province and territory when calculating WCB. These limits cap the amount of earnings subject to WCB premiums per employee, based on their province of employment (as defined in the work assignment). If provided, historical_remuneration is used to improve year-to-date calculation and help anticipate when the provincial cap will be reached. Once the cap is reached, WCB premiums will no longer accrue for that work-assignment, in that province or jurisdiction, for the remainder of the year.

​
Sample Request

To enable WCB calculation for British Columbia: 
  curl --request POST \
     --url https://sandbox.nmbr.co/services/payroll/tax_properties \
     --header 'Authorization: Bearer <access_token>' \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --data '{
          "owner_id": <work_assignment_id>,
          "effective_from": "2025-01-01",
          "type" : "ca::bc::workers_compensation_class",
          "value" : {
              "rate" : 2.1,
              "code": "88500",
              "industry": "Software development",
              "historical_remuneration": 1250000
          }
        }'

​
WCB Calculation

Once enabled, WCB is calculated per payroll and per province. WCB is calculated only on remuneration that is considered insurable under WCB rules, based on the province of employment defined in the work-assignment. The following values are used:
  • Payroll remuneration – Total insurable earnings in the payroll, by province.
  • Rate – The WCB rate provided in the tax-property.
  • Classification code and industry – For reference and reporting.
  • Provincial maximums – premiums are capped at the maximum insurable earnings per employee per year, based on province of employment.
  • Historical remuneration – Used to calculate the total to-date remuneration for the work-assignment in the province of employment.
When WCB is enabled for a work-assignment, a line item of type wcb will be created under employer_statutory_withholdings on the pay stub.
Once the annual cap is reached, no further WCB premiums will accrue for that work-assignment in the applicable province for the remainder of the year.

​
Remittance

In Quebec, CNESST premiums are remitted directly to Revenue Quebec by Nmbr along with other statutory remittances. For other jurisdictions, Nmbr can handle automated remittance for select workers’ compensation providers.

​
Enabling Automated Remittance

For Nmbr to remit on your behalf, the workers’ compensation Remittance Account must exist and its information must be accurate, including last_payment_amount in its metadata. Set last_payment_amount to the amount of the last payment made to the board before Nmbr takes over, whether you made it manually or a previous provider did. Remittance Accounts are sometimes pre-seeded for you. Look for an existing workers’ compensation account before creating one. Find an existing account 
curl --request GET \
   --url 'https://sandbox.nmbr.co/services/payroll/remittance_accounts?business_entity_id=<business_entity_id>&category=ca_workers_compensation' \
   --header 'Authorization: Bearer <access_token>' \
   --header 'accept: application/json'
If none exists, create one with account_provider set to your province’s board (for example, ca_on_workers_compensation for Ontario’s WSIB). Set the last payment amount 
curl --request PATCH \
   --url https://sandbox.nmbr.co/services/payroll/remittance_accounts/<remittance_account_id> \
   --header 'Authorization: Bearer <access_token>' \
   --header 'accept: application/json' \
   --header 'content-type: application/json' \
   --data '{
        "metadata": {
            "last_payment_amount": "1250.00"
        }
   }'
last_payment_amount is specific to workers’ compensation accounts and is returned in the account’s metadata.

​
WCB Reporting

Estimated WCB premiums are included in the workers-compensation report.