Registering a UK trademark in one class would cost you £170 for online applications, £200 for a paper application or £200 for the Right Start (online) application.
With the Right Start application, you pay half the fee upfront and receive an examination report prepared directly by the UKIPO. Then, if your mark meets the criteria for registration and you're allowed to proceed in the process, you pay the second half of the fee.
Please note that these fees are just the government fees paid directly to the UKIPO. Additional fees will apply if you use a lawyer, a law firm, or an online legal service to file your application.