What happens to my iCloud data if I stop my subscription?

If you stop paying for iCloud, your account will automatically downgrade to the free 5GB plan after the current payment cycle ends. If you have more than 5GB of data, iCloud will stop syncing new files. You'll have around 30 days to either reduce your data usage or to renew your subscription before Apple starts deleting excess data, starting with the oldest files. Make sure to free up space or back up your important data!

Remember, iCloud is more of a syncing service rather than a true backup solution. If your device is set to optimize storage, the full-resolution photos may only exist on iCloud, so keep that in mind when planning to downgrade. Just ensure you have copies of anything crucial!

Just a heads up, all new backups and syncing will halt once your data exceeds the free storage limit. During the grace period, you should delete unnecessary files from iCloud, especially from the 'Recently Deleted' folder. You can also download your data to keep it safe on another device before the deadline hits.