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You will certainly be UK tax resident based on what you have told me, ie 3 days per week in the UK so you will have to pay UK tax on your Swiss salary. However, you will be able to deduct the Swiss tax from your UK tax liability on the same income under the terms of the tax treaty between the UK and Switzerland. You will need to complete a self-assessment tax return.
The first £11,000 of your UK earnings will be tax free in the UK. The next £32,000 will be taxed at 20%. The next £118,000 will be taxed at 40% and anything in excess of £150,000 will be taxed at 45%.
I hope this helps but let me know if you have any further questions.