Does a replica still beat a cross-region pull?

Teams search for “S3 cross-region replication cost” after a job in another region re-reads the same bucket every month. Keep-pulling pays cross-region transfer on every gigabyte that leaves. A replica pays a one-time seed, then storage and any change-sync. Internet/CDN egress is a different page; this one is only region-to-region.

On the default 500 GB dataset — 800 GB pulled a month at $0.02/GB, replica storage $0.023/GB-month, 20 GB of monthly changes — keep-pulling is $16.00. The replica path is $11.50 of storage plus $0.40 of change-sync, $11.90, after a $10.00 seed. The replica path is $4.10 cheaper this month. The seed pays back in about 2.4 months. Over 12 months including the seed the replica path is $152.80 versus $192.00, $39.20 cheaper. The paths match at 595 GB of monthly pull. At 400 GB of pull, keep-pulling is $8.00 and the replica path stays $11.90. Paste the rates on your current price sheet. This page does not fetch provider prices.

Path	Seed	Storage	Change-sync	Monthly total	Horizon total

Complementary to the two-provider monthly comparison (which object store), CDN vs origin (internet downloads), and infrequent access vs standard (retrieve fees after a class change). This page is only a second-region copy versus pulling the same bytes again. The calculator is arithmetic, not advice. It does not claim a replica will stay in sync at the change volume you typed.

Common questions

Does S3 cross-region replication cost less than pulling the data every month?

Only when the monthly pull is large enough to cover replica storage and change-sync. On a 500 GB dataset pulled 800 GB a month at $0.02/GB, keep-pulling is $16.00. A replica at $0.023/GB-month plus 20 GB of monthly changes is $11.90 after a $10.00 seed. The replica path is $4.10 cheaper this month. The seed pays back in about 2.4 months. Over 12 months including the seed the replica path is $39.20 cheaper ($152.80 vs $192.00). The paths match at 595 GB of monthly pull. Paste your quoted rates; this page does not fetch provider prices.

When does keeping the cross-region pull stay cheaper?

When monthly pull volume sits below replica storage plus change-sync, divided by the cross-region rate. On these defaults that floor is 595 GB/month. At 400 GB of pull, keep-pulling is $8.00 and the replica path is $11.90, so keep-pulling is $3.90 cheaper this month. The page solves that volume from the rates you enter. It does not recommend turning replication on or off.