In some jurisdictions, the DOS is the date one continue to live together under one roof as house mates.

In general there are three types of separation: trial, permanent and legal, and each has a potential to affect the legal rights of the parties. More to the point, the date of each is very important.

Some couples agree to a separation.

A preponderance of evidence is satisfactory to prove this.

A legal separation, which is available in some jurisdictions, confers a different legal status on the spouses who are not free to marry again.

Different jurisdictions establish different criteria for a separation, but the date can make a big difference in the value of property distributed as part of the divorce settlement. The separation date can have an impact on the active and passive appreciation of assets subject to distribution.

In most jurisdictions, in order to obtain a no-fault divorce a couple must live "separate and apart" for a specified period. However, some jurisdiction have held that couples can separate "under the same roof"; that is, they have made the decision to end the marriage, gone separate ways but remained domiciled in the same house, usually for economic reasons.

Depending on the jurisdiction, a separation.

Salient here, however, is the DOS, after which the separate property.

Good legal advice is very helpful.