If you are married or living together as common-law, you can legally change your last name by completing an Election to Change Surname form.

If you are common-law, you will also need to file a form called a Joint Declaration of Conjugal Relationship.

Once the change is made, your Ontario birth certificate will show your new name and your previous last name.  This is the only difference between a legal name change and assuming a married name.

Also, common-law couples who want to change their names must do so legally, as they do not have the option to assume.

There is no fee if you legally change your name within 90 days of the date of marriage or of filing a joint declaration of conjugal relationship.  However, if you legally change your name after 90 days following marriage or of filing a joint declaration of conjugal relationship, the fee is $25.

How do I legally change my name back?

You can also change your last name back if you are currently married, separated, or in a common-law relationship by filing an Election to Resume Former Surname form.

You can resume your former surname if:

- You changed your name using the Election to Change Surname form or if the relationship has ended by divorce, splitting up if you’re common-law, or death of a spouse.

You have 90 days to change your last name back after this happens, or else you will need to apply for a Formal Adult Name Change.

If you complete an Election To Resume Former Surname form within 90 days of the date of divorce, the fee is $25.  To legally change your name back if it has been more than 90 days after the date of divorce, you must pay $137 for a Formal Name Change.

The service delivery time for both processes is usually 6 to 8 weeks.

To apply, you must phone in to the Office of the Registrar General toll free at 1-800-461-2156 or in Toronto at 416-325-8300 to get forms sent to you in the mail.