Cheapest cloud storage
Plan names include the storage on the price page. This list does not convert that into a price per gigabyte.
Verdict
iCloud+ 50 GB at $0.99/mo is the lowest monthly run rate in this list, $0.99/mo. iCloud+ 50 GB: The smallest paid tier.
Lowest plan on each service
Rank is a monthly run rate of a published price: a monthly price as billed, an annual price divided by 12, a charge every three months multiplied by 4 and divided by 12, and a charge every four weeks multiplied by 13 and divided by 12. The price column is the published charge.