Codebar - workshops and meetups with coaches to help you with your own projects, or guide you through their coding tutorials (with a goal to enable underrepresented groups to learn programming).
Keep Calm and Carry on Coding - a fortnightly meetup aimed at anyone have who has recently done a coding course and wants to continue learning.
Code && Cake - regular meetups where you can work on your own coding side projects whilst eating cake (hurrah!); open to all experience levels.
Women Hack for Nonprofits - work on collaborative coding projects for nonprofits (ususally web dev); very keen for you to learn new things in the process and open to beginners.
Women Who Code - promoting women in technology, with coding workshops and events.
Ladies of Code - monthly talks from leaders in the field and coding/hacking sessions, "discussing some pretty in-depth, geeky stuff".
Blackgirl.tech - a meetup for black women and girls living in London and working in or transitioning into technology.
Code First: Girls - as well as free courses for young women, CFG hosts 'Hack Your Career' events.
Mums in Technology - coffee talks, workshops and a coding school for mums; children welcome!
Girls in Tech UK - focused on the broader tech and entrepreneurship scene and careers (including non-programming tech roles), with monthly events and a leadership programme.
Language/framework specific
R Ladies - a meetup for the statistical programming language R.
PyLadies - informal sessions, workshops and study groups to learn Python through small projects, as well as talks (aiming to support more women and genderqueers to become active participants and leaders in the Python open-source community).
Rails Girls - free 1.5 day workshops on web development with Ruby on Rails.
Django Girls - free two day workshops for complete programming beginners on web development with Django (a Python framework).
Women Who Go - for women interested in the Go programming language, with monthly meetings, talks and beginner workshops.
Women in VR - networking group for women working in Virtual Reality, Augmented Reality or other immersive technologies (also with meetups in Manchester).
About this list
This list was originally put together by Jenny Brennan and is open to contributions (see below).
The focus is on meetups suitable for beginners, as well as women-majority events, as it started from lists sent to classes at the end of my Code First: Girls courses.