You can use your mobile phone from abroad in Turkey for up to 3 months with a Turkish SIM card, after which it will be blocked. To avoid this ban, you can register your phone in Turkey, which costs 2,732 TL in 2022 and 6,090 TL from 2023. To register, first get an e-devlet access with your Ikamet – if you don’t already have it. Then go to the tax office (Vergi dairesi). There you need to have your Ikamet, your e-devlet access and your passport and of course the phone you want to register and pay the corresponding amount. Keep the proof of payment safe! After that, register the phone on www.turkiye.gov.tr or do it in the nearest phone shop.