Be aware that your employer will be required to pay the same social security charges as a French company. It’s not just you, as an employee, that pays more tax.
In my case, my employer asked me to take a pay cut until their tax liability in France matched the same as when I was a UK-based employee.
I have lived in France for 20 years - work for a UK company for more than that time - wages paid into UK bank account but pay all my tax here is France. I have a cds and had no problem getting that. I have no property etc in UK .
I declare it all in May as per and when I changed to French tax years ago got a rebate from UK.
I got a form from HMRC and stopped my PAYE in UK - they gave me an NT tax code.
Has to be worth an ask at HMRC.
If you are economically active but are not paying cotisations and do not have an S1, I cannot see how you will qualify for healthcare in France.
@Maggie1
Hi I think you may be answering the wrong person - I’m a boring French civil servant with no weird tax situation 
Is the UK company registered in France, or are you a posted worker or frontalier with a worker’s S1? How is you social security covered? As that is the issue for the OP.
One can work for whoever one likes here as long as the correct social security is paid.
Hi. If you are on Facebook, I suggest that you join the group ‘Strictly Fiscal France’ to find the correct advice for your situation. There are extremely helpful experts, guides as well as lots of posts from people in exactly the same position as you.
No its the UK part of an international company - pay my health insurance here but I do get a UK pension which is paid in UK. So maybe different for me as I am retired but do a fulltime job of 35 hours plus a week.
S
Thought I had a simple answer but it looks more complicated - so I will bow out of this conversation.
From what you have said so far I was thinking that you are in a very specific and possibly unusual situation that would be impossible to replicate now. Just the fact that the company is international makes a difference. So agree your experience may not be relevant for OP.
Is there an avenue / mechanism for me to do this, but efficiently and legally? As in, still get paid GBP into my UK account, but instead of paying HMRC I pay social security to France instead?
Amazing suggestion, thank you!
Is there an avenue / mechanism for me to do this correctly, while still being paid GBP into my UK bank account?
I’d like to avoid any additional admin for my current company, as they’re stretching already to allow me work fully remote from France.
Hey Maggie, saw below that you think this might not be relevant to our situation, why is that? Because it sounds kind of perfect!
Interesting, have you a ball park idea of what the extra cost to them was, even in % terms?
Also, how did they go about doing it, e.g. did they set up new French entity just for you?
Very interesting again, thank you. Did you employer engage URSSAF themselves?
Did that make you effectively an employee of URSSAF?
It was ages ago now but I think I jusr contacted HMRC said I was living in France and filled in a form etc and have an NT tax code as I pay it all here. As I don`t have PAYE in France I pay my years tax over 4 months. That has been worked out by the French tax office and it just comes out of my bank acct
My daughter might remember exactly what we did back then so will ask her and pass on any further info if there is any.
My company also has people in New Zealand who do the same as me so there must be a system somewhere.
Yes, there is a simple system for employers without a base in France to declare and pay social security. But please din’t underestimate the difference that Brexit has made!
For Jimmy Prideaux this is what the employer needs to do for you, and them, to be legal. It will cost them a chunk, which is why some employers won’t donit so you are left with the more expensive portage salarial
https://www.tfe.urssaf.fr/portail/en/accueil/s-informer-sur-offre-de-service/essentiel-du-tfe.html
I’d rather not disclose actual amounts but I can say that my salary was reduced by 20% to ensure that their tax liability remained the same.
Yes, we set up a French entity via URSSAF. It’s very straightforward and they have documentation in English and German as they know not everyone speaks French.