Easiest way to migrate aliases from bash to zsh I want to start using zsh as recommended by Apple for Mac OS Catalina. How do I migrate my aliases that I have defined in the ~/.bash_profile to the new shell?
If until now you've been using ~/.bash_profile for the loading the aliases, here are some of the ways you can migrate your aliases:



 1. Copy the contents:

The most assiduous and obvious way is to copy the contents of your ~/.bash_profile  to ~/.zshrc. It works particularly when you are moving on from bash to zsh for good.



 2. Pull out aliases and then source them:

Another *way is:


Create a new file that will contain the aliases (let's call it ~/.aliases);
Copy the contents of ~/.bash_profile to the new aliases file;
Modify the ~/.bash_profile and ~/.zshrc to source the new file.


Put the following in ~/.bash_profile:

if [ -f ~/.aliases ]; then
   . ~/.aliases
fi


and put the following in ~/.zshrc:

source $HOME/.aliases


This way the aliases will be available for both shells. More importantly, if you make changes to the aliases, the changes will cascade to both shells automatically.



* Taken from here