My exH has had a tax demand which relates to the period while we were separated but still married. He is claiming I benefited from my share of the increased net amount as all earnings at this time were split 50:50 and he is asking for me to pay half of the tax demand.
Presumably you're divorced as you call him your ex.
Did you get a financial settlement and a court order?
The short answer to your question is no. You were separated, so if he spent all his income then tough, but it might be a liability that might be taken into account by any judge dealing with the financial split.
Thanks for responding. Yes we are divorced and there was a financial agreement and a court order.
The tax is owed on a one off payment and it looks as though his employer got the calculation wrong.
This payment wasn't really taken into account in the financial settlement but it was joint earnings used to pay joint liabilities while we were married but separated so as he sees it I got half of the too big amount so I should pay half of the tax.