I think you can get a discount on NCT classes in certain circumstances but most I've seen in Bristol are about £300! I need to do antinatal classes but if they are online due to covid that seems like a lot!!!
I’m Bristol based and was happy to do mine online, my (Southmead) midwives sent me an email with a PowerPoint and videos and links when I was about 28ish weeks.
Also the midwives at the RUH posted their antenatal classes called Hello Baby online on YouTube for free at the start of lockdown which I highly recommend. Really thorough and easy to follow, DH and I both watched them all and loved them.