Ownership changes

NEW: You can now submit account documents and send messages to us through our online services.

Change in business type or partners in a partnership

Business type changes (changes to a legal entity) can include a sole proprietor incorporating or forming a partnership, or a partnership incorporating. When this happens, you must create a new account and we'll need to complete a review for a possible transfer of experience between accounts.

If you’ve changed the type of ownership for your business, please provide the following information using our online services or email them to us at employeraccounts@wsib.on.ca, noting your account number in the subject line of the message: 

  • account number in the subject line of the email
  • details of the ownership change (including new legal name)
  • date you began operating under the new legal entity
  • date you ceased operating under your previous legal entity
  • any changes to the business activity
  • all owners under the new corporation or partnership
  • number of employees (if applicable)

An addition or removal of partners in a partnership also affects your account. If this happens, we need to be informed in writing of the partnership name change, along with a copy of the partnership agreement.

Next steps

We’ll review the ownership change details to determine if the account should be updated or if a new account is necessary. You‘ll receive a registration letter in the mail with the new account details and a closure letter for the existing account outlining any next steps if a new account is needed. You’ll receive a confirmation letter as well as details regarding any impacts to your premium rate if the insurable earnings and claims experience of the original account should be transferred to the new account.

Change of executive officers in a corporation

A change in the executive officers in a corporation should be recorded in a corporate minute book. We require a copy of the minutes showing the appointment and/or resignation of the officer(s). 

If a corporate minute book is not available, we may review other documents, including resolutions by the board of directors, corporate by-laws, or public records filed with other government authorities (for example, Notice of Change by an Ontario Corporation, Form 1).

Please submit the documents online or email them to us at employeraccounts@wsib.on.ca, noting your account number in the subject line of the message.

Next steps

We'll make the required updates to the account. Please note, we won't send email confirmation.

Amalgamations and mergers

Amalgamations don't apply to sole proprietorships or partnerships. Two or more corporations may legally merge or amalgamate and continue as one corporation. This merger or amalgamation is registered with the Ministry of Government and Consumer Services and articles of amalgamation are issued. The new amalgamated corporation acquires all assets and assumes all liabilities of the merged or amalgamated corporations.

If your company has gone through a merger or amalgamation, you must provide the required documents online or email them to employeraccounts@wsib.on.ca, noting your account number in the subject line of the email:

  • all account numbers included in the amalgamation
  • the Articles of Amalgamation
  • the Articles of Amendment (if applicable)
  • which account(s) should remain open
  • any active accounts under the amalgamation that should be closed and the applicable closure date
  • any changes to the business activity

Next steps

Once we receive the Articles of Amalgamation and any other required information, we’ll complete the amalgamation and send you a confirmation letter. We’ll send further correspondence outlining the actions taken (for example, reclassification) if additional action is required.


For the purposes of classification and premium rate setting, we may determine that two or more businesses are associated and therefore treat their operations as if a single employer carries them out. This ensures that each business pays their appropriate share of costs to maintain the system.

Our Associated Employers’ policy requires the application of a two-part test for determining association. If two or more businesses meet both the test of affiliation and the test of cooperation, they are considered associated.

The test of affiliation considers business relationship factors such as ownership structure, profit sharing and control in corporations. The test of cooperation identifies whether there are any substantial connections, integration and/or dependencies between the operations of each organization’s business activities.

We'll use an association questionnaire to gather information to assess employers’ business activities and working relationships with one another.

Please send us a message online or email us at employeraccounts@wsib.on.ca, if you believe your business is associated with another business.

Next steps

We'll discuss the ownership structure of any affiliated business as well as any integration between the businesses. Once we receive the required information, if an association is determined, we'll combine the experience of all associated companies for rate setting purposes, and send a decision letter as well as any rate impacts based on the changes on your account.