We recommend that you purchase a resource plan when you can provide an estimate that is near your resource usage.

For example, you can estimate that you are about to use 100 GB of Standard locally redundant storage (LRS) quota in the following three months for all buckets of your Alibaba Cloud account. You can consider purchasing a Standard LRS plan of 100 GB for three months to offset storage capacity fees. Compared with the pay-as-you-go billing method, you can save more cost if you use a storage plan to offset storage capacity fees.