Nintendo provided further details about the Nintendo Switch Online service yesterday during the Nintendo Direct presentation. One thing that has been spotted with regards to cloud saves is that once your subscription expires, or you cancel, you will lose you cloud saves and they will be erased. Sony locks its cloud saves behind the PS+ membership but they are kept for around 6 months or so. Microsoft offers free cloud saves without an Xbox Live subscription. So you’ll need to keep your Nintendo Switch Online subscription up if you want to keep your saves backed up online otherwise you will lose your cloud saves.
Q. After my Nintendo Switch Online subscription expires, will my Save Data Cloud files and Nintendo Entertainment System – Nintendo Switch Online save data be erased?
A. Save data stored with Save Data Cloud cannot be kept outside of the duration of your Nintendo Switch Online membership. Nintendo Entertainment System – Nintendo Switch Online also uses the Save Data Cloud, so the same applies. However, if you keep the Nintendo Entertainment System – Nintendo Switch Online save data saved locally on your Nintendo Switch console, then you can use it again if you purchase another membership.