There is no document, per se, to confirm the date of a legal separation.
You are separated from your common law or marriage spouse as soon as one of you makes your intention to end the relationship clear to the other.
To be absolutely clear to your spouse that you are separated, you should put the date of separation in writing to your spouse. This can mean by text message or e-mail.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.