Legal gender change? (UK)

[RayaL]

I've recently begun to physically transition (HRT), and I've been to my GP and got a referral to Nottingham GIC, however, I'm trying to get the ball rolling and I've had my name changed for a while now, and lived as a woman for many years. However one thing thats bothering me (especially as I've started my transition) is that my gender is still listed as M . I've been researching online how to change your gender legally and I was wondering what you needed to provide and it says you need to be diagnosed with gender dysphoria, would I be able to just get a letter from my general GP as I haven't had an appointment at the GIC yet, and as you're all probably aware the waiting list is terrible

[Elis]

I went to a private GIC to get diagnosed but going the NHS route for my prescriptions while waiting for my NHS GIC appointment; so my GP knows I've been diagnosed with GD. So I simply asked her for a letter to say I'm FTM transgender and now living as male. I posted this letter along with the passport form along with another letter explaining I've changed my gender and want my new passport to reflect this (just in case of any confusion) and now have a passport that says male without a GRC. I don't see why your GP won't give you a letter seeing as you've had many years of RLE and on HRT. So yeah just ask