Thanks for your question.
If you are both named on the registered legal title to the property as the registered proprietors then ultimately your ex-partner could apply for the Court for a order for sale of the property. These orders are seldom refused unless there are children living at the property who continue to require the house for accommodation.
In the absence of any express agreement there is presumption that the proceeds of sale are split equally. This if either party contributed more the financing of the purchase or has maintained the majority of the mortgage repayments as you have then you may be able to rebut the presumption and they will receive more of the proceeds of sale. This is costly, time-consuming and stressful however. It is usually better to negotiate and settle unless one party is being particularly unreasonable in their demands.
Try to save yourself some legal fees by seeing if you can come informally to an agreement for a split in the equity that you can stomach.
It does take some time to force the sale of the property and you will receive probably a negotiated settlement which you can use to either receive a small mortgage offer for a small place or rent somewhere until you can receive the mortgage offer you require.
If you and you partner presently hold the house jointly (as joint tenants) then each person's share would pass to the other upon death regardless of any direction made in any Will. If this is not what you want then you should sever the joint tenancy by using Form SEV from the Land Registry (you will have to send it to them and if you have any questions about completing the form you should call their customer service number - they are very helpful):-
You will then hold you interests as tenants in common, meaning that your respective shares will pass according to their wills or under the intestacy rules. Your partner need not sign the form provided you follow the instructions.
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