[abraham]

Signal has had a backup to a file you can do any you want to for years.

[newscracker]

Never on iOS or any other Apple platform. Signal is designed not to be able to backup to iCloud either. The only option iOS users have had over the last few years is to do a device to device transfer where both phones are expected to be in physical proximity and it takes hours to transfer the data. Lost phone has meant losing all chats.

WhatsApp, which is infamous by association with Meta, backs up to Google Drive or wherever.