What is the difference between articles of incorporation and bylaws?

Both are fundamental documents, but they serve different purposes and live in different places.

Articles of incorporation are filed with the government — either the Ontario Business Registry or Corporations Canada — when you create the corporation. They define the corporation's name, registered office address, share structure (classes, rights, restrictions), any restrictions on the business the corporation can carry on, and the number of directors. Once filed, the articles are a public document. Changing the articles requires a formal amendment filed with the government, often after a shareholder vote.

Bylaws are the internal rules the corporation adopts to govern its own operations — how directors are elected, how meetings are held and noticed, what quorum is needed, how officers are appointed and removed, and how the corporation's business is generally conducted. Bylaws are not filed publicly (unless they are a unanimous shareholder agreement or similar restricted-access document). The board of directors typically adopts bylaws by resolution, which shareholders then confirm at the next meeting.

Think of the articles as the constitutional charter (public, harder to change) and bylaws as the operating rules (internal, more flexible). Most owner-managed corporations adopt a general bylaw at incorporation and rarely need to update it unless ownership or governance changes significantly.