How do I transfer my authenticator to another phone?

[Yukiko ~Snow Child~]

I removed it from my old phone and I want to put it on my new one. Is there a cooldown before I can add it?

[The End.]

Can I transfer my authenticator to my new phone?
Yes, you can.

To transfer your authenticator to a new phone, you'll need access to the phone number associated with your account (so we can send you a text message to confirm it's you).

From the Steam Mobile app on your new device, try to log into your account. When the app asks for your authenticator code, select "Please help, I no longer have access to my Mobile Authenticator codes." Follow the steps the app provides and you can either transfer your authenticator to the new device or remove it from the previous device.

After transferring the authenticator, any new trades or market listings will be held for a couple of days to protect your items in case your authenticator is ever transferred by a malicious person. See our Trade Holds FAQ for more information about trade holds.

https://support.steampowered.com/kb_article.php?ref=8625-wrah-9030#transfer