Tax-at-source in first year

I am soon moving to France. My income is pensions from the UK. Do I have to do anything tax-related in the first year and how should I declare the pensions?

You will not have any obligatory income declaration to make until April-June 2027 if you move in 2026. When you submit your first tax declaration you should also submit HMRC’s France-Individual form to your French tax office so your taxation can be transferred from the UK to France. 

Any tax for 2026 would normally be payable in autumn 2027 at which point you would also start paying instalments of tax-at source, related to UK state or private pensions once the tax office knows what kinds of income you have (assuming you have a high enough income not to have a 0% PAS tax rate). 

Strictly-speaking, the tax-at-source system only functions in the true sense (i.e money taken before payment) for French salaries and pensions and not foreign ones (as the source for these is out of France). However, for known, regular foreign incomes taxable in France there is a system of ‘on-account’ direct debit installments.

Once you have declared this income for a given tax year, regular PAS payments will be put in place after that. If you wish, you can set up a personal space at impots.gouv.fr shortly after arrival and begin paying installments based on estimates.

See chapter 4, section 'What you require to make first online declaration' for how to do this and sources of help. Relevant English-language services also advertise in The Connexion (including in the Business Directory). 

Subscribers of The Connexion can access this information via connexionfrance.com/subscriber-resources.