Hello, my name is Jim and I am a qualified lawyer happy to help you this evening.
If the period of cohabitation and marriage is 5 years or less, the courts are generally of the view the pre-marital assets should not be shared. For longer marriages, the court would look at contributions of each party but you cannot exclude the deposit entirely (though you would have an argument that you paid the deposit and should have it back).
Your case is that you should have your deposit back plus 50% of the equity after sale costs.
You can either apply for a judicial separation (and then a financial order), or a divorce (if you want to dissolve the marriage) and again, apply for a financial order.
If you disagree and cannot come to an agreement, you can ask the local family court to assess a split of the finances and also to deal with the property.
Assuming your husband eventually agrees to a settlement then you can have a consent order drawn up to bind the parties to the agreed terms.
The court will consider Section 25 of the Matrimonial Causes Act 1973 when it assesses a financial settlement. Therefore your ages, length of marriage, any children under 18, your earnings and earning potential (same for your husband), the assets including the former matrimonial home and pensions if applicable, any debts, financial and non-financial contributions to the marriage, your standard of living enjoyed before the marriage breakdown, your financial needs in future and your housing needs, and so on.
The starting point is 50% but if there is a disparity in earnings or you have paid more in the way of mortgage/rent, etc, you can ask for more than 50% of the former matrimonial home like I said earlier. It would be worth speaking with him to see if he would agree to any split without having to involve the court.
If nothing can be agreed then you would need to issue financial remedy proceedings once decree nisi comes through (if you start divorce proceedings), or obtain a decree of judicial separation, so you ask the court to become involved in a financial settlement as well as the divorce.
Before you do this you need to contact a local mediator which is compulsory before you ask the court to intervene in the financial aspect. You can find a local mediator here :
Assuming mediation fails or your husband doesn't agree to mediation then you will need to issue financial remedy proceedings and you would need to complete and send two completed copies of Form A (one copy is attached) to your local family court and pay a fee of £255 payable to HMCTS. If you are on a low income or have low savings you can ask the court for help with the fee here https://www.gov.uk/get-help-with-court-fees
The court will then list a first appointment and give directions for a financial dispute resolution hearing (FDR) where the judge will give their opinion on a likely settlement - which usually prompts a settlement at this stage. The court will ensure the parties make full and frank disclosure of their assets and liabilities to ensure the financial positions of you both are known and to allow the court to make a settlement decision. If the case does not settle, further directions will be given and a final hearing may take place if neither of you can agree to settlement terms.
To apply for a judicial separation, the site is here: https://www.gov.uk/legal-separation
To apply for a divorce, the site is here: https://www.gov.uk/divorce
And for information on a financial order: https://www.gov.uk/money-property-when-relationship-ends/apply-for-a-financial-order
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