Does my Ontario corporation need to have a corporate seal?

No. Under the Ontario Business Corporations Act, a corporation is not required to have a common seal. The Act was amended years ago to remove the mandatory seal requirement. Documents that used to require a seal — such as share certificates and certain contracts — can now be validly executed by the authorized officers of the corporation without one.

However, many corporations still choose to have a corporate seal as a matter of tradition or practice. Some third parties (particularly in real estate transactions or across international contracts) may expect or request a seal. Having one is not a legal requirement, but it is not prohibited either.

What does matter for executing corporate documents properly is ensuring that the right people sign. Corporate bylaws or resolutions should clearly identify who has authority to bind the corporation — typically a combination of officers such as the President and Secretary for ordinary documents, with higher-level authorization required for major transactions. If a contract is signed by someone who does not have proper authority, it may not bind the corporation. Reviewing your authorization procedures with a lawyer is more important than whether you have a seal.