Thanks for your question.
No, one can just write to the bank and remove themselves from the mortgage/legal title. A formal Land Registry TR1 form must always be executed in order to do this.
In any event, if you have been married to your husband for 20 years then the marriage is classed as a "Long" marriage for the purpose of matrimonial settlement pursuant to any divorce that should occur. This means that all assets of each person acquired both prior to and during marriage are included in the matrimonial pool of assets over which settlement shall be negotiated.
There is a presumption in long marriages that each party shall receive 50% of those assets. This presumption can be rebutted largely if there are minor children that shall reside with one party or, to a much lesser extent, if one party requires more income/assets because they have a health condition that requires this.
This means that you would be entitled, most likely, to 50% of the equity, but this may vary depening on the aforementioned rebuttals. You need to speak to your husband about going to mediation in order to reach an amicable settlement or a solicitor if he is unwilling to mediate.
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