First of all, 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.
She has to receive a mortgage offer in her sole name in order to transfer the property from your joint names in to her own. If there is equity in the property then you can attempt to negotiate a settlement to reflect your share of this.
Ultimately, you can force the sale of the property by making (or posturing to make) an application to Court. If your partner cannot demonstrate sufficient finance to receive a mortgage offer to buy you out and transfer the equity in to her name then this may be your only option. A local solicitor would be able to do this for you and these orders are seldom refused by the Court.
If she is not making effort to get a mortgage offer then you should see a local solicitor about writing to her stating that she should be doing so if she wishes to take it over and to continue living there, as well as making her aware that you will apply to Court for an order for sale if she does not.
Hopefully this will prompt her compliance, if it does not then you will be forced to apply to Court for an order for sale.
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