The fees are set out in Article 46 and Annex 2 of the Ordinance on Identity Documents for Swiss Nationals (SR 143.116). These are payable in the currency determined by the Swiss representation.
Fees
Regional Consular Centre London: fees for Swiss identity documents (PDF, 2 Pages, 181.1 kB, English)
All fees must be paid at the time of the appointment. Credit and debit cards accepted (no American Express).
Passports and ID cards are posted separately due to different locations of production.
The Swiss representation reserves the right to adapt the amounts at any time in relation to exchange rate fluctuations.
Ordinance on Identity Documents for Swiss Nationals (de, fr, it) (VAwG; SR 143.11).