This week's expert is Patricia Robinson
BBC News' Ask the Expert column gives readers a chance to have their financial questions answered.
This week's expert is Patricia Robinson, a matrimonial lawyer with national law firm Laytons.
Your Money reader Jackie Plumber would like some help. Her son's partner has left him and is refusing to contribute to a joint mortgage.
What should Ms Plumber's son do?
Patricia Robinson replies:
It is important that your son does not bury his head in the sand and takes steps to sort out the ownership of the flat as soon as possible.
When a couple purchase a property in joint names with the mortgage, they will be jointly liable.
This means that the mortgage company can pursue both or even just one of them for the payments.
If the mortgage payments are not met they will both be at risk of a bad credit rating and, ultimately, the flat could be repossessed. This should be avoided at all costs.
However, he should not continue to meet the payments on the mortgage long term while the ownership of the flat remains in joint names.
As your son does not want to sell the flat, he needs to make enquiries with the current mortgage company to see if they will consent to the transfer of the property into his sole name subject to the mortgage.
To do this he will require his ex-girlfriend's co-operation.
As it is a joint property, the ex-girlfriend will need to consent to the transfer into his sole name.
However, before proceeding with the transfer he should make sure that he can afford the mortgage repayments on his own.
New mortgage option
One option is to approach other mortgage companies to see what remortgage deals they can offer.
Many mortgage companies offer very attractive deals, and he may find that he would be able to take out a new mortgage in his sole name which will discharge the existing mortgage and will result in cheaper mortgage payments.
As there is no equity in the flat, the ex-girlfriend will no doubt be anxious to ensure that she is released from any further liability in respect of the flat.
Your son's offer to take over all financial responsibility for the flat should therefore be appealing to her.
Whether he decides to take over the flat by transferring the existing mortgage to his sole name or by taking out a new mortgage with his girlfriend's consent, the legal ownership of the flat should transfer to him at the same time.
He will need to instruct a solicitor. Some mortgage companies will include the instruction of a solicitor to do this when taking out a new mortgage.
If, after making the necessary enquiries, he finds that he cannot afford the mortgage payments on his own, the only other option is for the flat to be sold.
To do this, he will require his ex-girlfriend's consent and co-operation to the sale.
If she refuses to co-operate with the sale of the flat, it will be necessary for an application to be made to the court for an order for sale.
This can be a very costly exercise and should be avoided if at all possible.
Whilst your son is deciding what to do, he should approach the mortgage company and explain his predicament.
Under the terms of the mortgage it may be possible to reduce the monthly payments by converting to a repayment mortgage (if that is what it is) to interest only or, if the mortgage has been running for some time, taking a mortgage holiday.
Should the end result be that the flat is transferred into his sole name and his ex-girlfriend's name is no longer on the mortgage, your son will be solely responsible for the mortgage payments.
He will therefore need to ensure that these are met.
Should the mortgage run into arrears, he will then be at risk of the flat being repossessed.
It is therefore imperative that legal advice is obtained, and also thorough financial advice from an independent financial adviser before deciding which steps to take.
He should do this as soon as possible. Once he is aware of his options he can then approach his ex-girlfriend on how he wishes to proceed.
The opinions expressed are those of the author and are not held by the BBC unless specifically stated. The material is for general information only and does not constitute investment, tax, legal or other form of advice. You should not rely on this information to make (or refrain from making) any decisions. Always obtain independent, professional advice for your own particular situation.