Policy in practice: Premium frequency

Businesses report their insurable earnings and pay their premiums monthly, quarterly or annually, depending on the estimated amount of their annual insurable earnings. Businesses that report monthly must complete an annual reconciliation by March 31 of every year. If you close an account during the year, you must complete a reconciliation form, regardless of your reporting frequency.

Below you will find examples of scenarios to help you understand our billing cycles including information about:

This is not a policy. If there is a conflict between this information and our policy on premium remittance, the decision maker will rely on the policy.

Premium frequency for businesses with multiple accounts

If a business as one legal entity has multiple WSIB accounts, one reporting and payment frequency will be assigned for them all. We use the sum of the annual insurable earnings of all of the individual accounts of the same legal entity to determine the overall premium frequency.

Example 1: one legal entity has multiple WSIB accounts

Scenario: Francois owns and operates three pharmacies. The legal name of each pharmacy is the same. They are located at three different addresses and have dedicated staff. Francois has a separate WSIB account for each of his pharmacies. Francois reported the following insurable earnings for each account for the prior calendar year:

Account 1 = $18,500

Account 2 = $563,500

Account 3 = $434,250

The total insurable earnings for all accounts = $1,016,250.  The total annual insurable earnings for all three of Francois’ accounts are $1,016,250.  Because this amount is more than $1,000,000, Francois must report and pay his premiums monthly.

However, if the three pharmacies at three individual locations were owned by different legal entities, account one would be assigned an annual premium frequency, and account two and three would be assigned a quarterly premium frequency, based on the premium frequency thresholds.

Premium frequency for businesses registering with us

If you are registering your business or reinstating a previous WSIB account, you must estimate your insurable earnings for the calendar year. The thresholds below will determine the frequency based on the amount estimated.

Premium frequency thresholds

Insurable earnings (current year)

Premium frequency (reporting and payment)

$1,000,000 or more


$20,000 to $999,999.99


Less than $20,000


Example 1:  a newly registered business estimates their insurable earnings (annual reporting)

Scenario: Shiny Object Inc. registers with us and provides estimated insurable earnings of $19,000 for a full calendar year. As a result, they will report their annual estimated insurable earnings for their workers and pay their premium for those earnings once a year by the end of April.

Example 2: A newly registered business estimates their insurable earnings (quarterly reporting)

Scenario: in October, Maria opens a small clothing store and registers with the WSIB providing estimated insurable earnings of $8,000 for the remainder of the year, and $34,000 for the full calendar year ahead.
Since the estimated amount falls between $20,000 and $999,999, Maria will report and pay her premiums quarterly. Maria must report the actual insurable earnings of her employees each April, July, October and January.

When does the WSIB change business’ premium frequency?

Once a year, the WSIB reviews the reported insurable earnings of all business with an annual or quarterly premium frequency to determine if the premium frequency should be increased. If the annualized insurable earnings are $1,000,000 or more, the reporting and payment frequency of the business will be automatically changed to monthly by the WSIB, effective January 1 of the following year.

For businesses that report quarterly, the actual insurable earnings are derived from the earnings reported in the first nine months, annualized to a full calendar year.

For businesses that report annually, we use the final reported annual estimated insurable earnings for the prior calendar year.

Example 1: changes to premium frequency based changes to annual insurable earnings

Scenario: Joshua registered with the WSIB in March and estimated his annual insurable earnings as $360,000.  The premium frequency was set at quarterly. From January 1 to September 30, Joshua reported actual insurable earnings of $860,000.
In November, we reviewed his account and his annualized actual insurable earnings of $1,149,816.85 ($860,000 x 365 ÷ 273*) to determine his premium frequency for the year ahead.

Joshua’s annualized insurable earnings are more than $1,000,000, so the WSIB lets Joshua know that his premium frequency will change to monthly effective January 1, the following year.  Joshua must still report and pay for his last quarterly remittance that is due by the end of January.

*273 = September 30 is the 273rd day of the year

Lump sum prepayment

Although businesses with insurable earnings of $1,000,000 or more must report and pay their premiums monthly, they may apply to make a lump sum prepayment of their premiums by completing and submitting a
. This will allow you to prepay your total premiums once a year rather than monthly.

Verifying information  

To verify reporting accuracy, we can request information from you, including the following:

  • Ownership documentation (e.g., Corporate Minute Book, Business or Partnership Registration)
  • Payroll records, such as T4’s, T4A’s, T5’s, Statement of Investment Income and payroll journal(s)
  • T5018, Statement of Contract Payments
  • Clearance Certificates obtained for all retained contractors
  • Prepared financial statements, including Statement of Business Activities or Profit and Loss Statement
  • Contractors’ invoices/contracts and clearance certificates, etc.
  • Cheque registers or cash disbursement journals

Any inaccurate information provided to the WSIB may be considered a lack of disclosure or making a false statement and can impact the period of premium adjustments made to your account. To learn more see our Employer Premium Adjustments policy.

The WSIB and the Canada Revenue Agency (CRA) exchange information to maintain the integrity of their systems and ensure a level playing field for Ontario businesses.