Appoint or cancel an Ontario tax representative without retyping both parties' details

Taxpayers appointing or cancelling a Ministry of Finance representative repeat legal names, addresses, account identifiers, and representative contact details on every authorization package. This guide is an example of storing them once in hivi.

Official form and source

Start from the official source and always use the current version — form numbers and links can change:

• Service page: Corporations tax forms and publications — ontario.ca
• Form (Central Forms Repository): Authorizing or Cancelling a Representative — 9966

What this form is about

Form 9966 is Authorizing or Cancelling a Representative for Ontario Ministry of Finance tax programs — confirm which authorization form your account requires on ontario.ca.

Before you start: what to gather

• Taxpayer legal name and mailing address.
• Business number or Ontario tax account identifiers if applicable.
• Representative name, firm, address, and contact details.
• Authorization or cancellation date and scope — confirm on ontario.ca.

Confirm the current process on ontario.ca.

How hivi makes it faster

1. Save it once. Store your taxpayer and representative name and address details in your hivi profile.
2. Keep documents ready. Upload supporting documents to hivi Files so you are not searching at form time.
3. Autofill the form. Use the hivi Chrome extension on a web form, or fill a PDF from your saved profile inside hivi.
4. Review and submit yourself through the official channel.

Why do it in hivi

Related Ontario forms repeat the same personal details. Captured once in hivi — stored in Canada, with AI on its own servers — every form starts mostly complete.