In the UK on an £80k ($108k) salary an employer would have to pay 89,820.08 ($120222), plus pension contributions and the employee would receive £55,092.76 ($73740)
In California someone paid $120k Gross I think would receive $79548, before healthcare deductions (optional private healthcare in the UK is typically about $700 a year for a single person of working age, in the US I believe premiums (employer and employee) are more like $7000 a year)
Overall at the $120k range it seems a similar cost in the UK vs California. Office space in London is probably higher than in SF, but that doesn't apply for remote workers.
In California someone paid $120k Gross I think would receive $79548, before healthcare deductions (optional private healthcare in the UK is typically about $700 a year for a single person of working age, in the US I believe premiums (employer and employee) are more like $7000 a year)
Overall at the $120k range it seems a similar cost in the UK vs California. Office space in London is probably higher than in SF, but that doesn't apply for remote workers.