I'm trying to permanently change my shell to zsh using chsh command, but it's not working.

zsh is installed (via apt) and works fine when I invoke it directly from a bash prompt terminal. But I can't get zsh to load in terminals by default, and chsh is doing something weird:

$ echo $SHELL

/bin/bash

$ which zsh

/usr/bin/zsh

$ chsh -s /usr/bin/zsh

Password: 

$ echo $SHELL

/bin/bash

$ grep kurtosis /etc/passwd

kurtosis:x:1000:1000:kurtosis,,,:/home/kurtosis:/usr/bin/zsh

It appears chsh has managed to correctly change /etc/passwd, but not the $SHELL env variable. As such, new terminals always start in bash and not zsh.

I'm not sure where to look to troubleshoot this. .bashrc, even though it's not invoked until the shell is specified? Any help appreciated.