Run the three-way cost recompute before Fly.io's 20% RAM hike hits your October invoice

The email is a pricing decision

The email in your inbox is a margin call. Fly.io notified customers on September 21, 2026, that Fly Machines memory prices would rise 20 percent on October 1, 2026. CPU prices on Fly Machines would not increase. For unmanaged Fly Postgres, the database is a Fly Machine plus a volume, so the memory increase applies to the Machine memory line for that database. The memory line is the part that changes, which makes the choice a margin recompute, not a support ticket.

The invoice shows what changes

Before you resize anything, separate the lines that change from the lines that do not. Provisioned Fly Volume capacity is billed at $0.15 per gigabyte per month. Volume snapshot storage became billable on January 1, 2026, with the first costs showing up in early February 2026. A year of the same machine size makes the old total a weak baseline. The new baseline is the memory line after the increase, plus the unchanged lines around it.

Profit and cash are different animals. A margin line can look healthy in the spreadsheet and still feel tight when the invoice arrives. A small price change is easy to ignore, but it can change the habit of checking the bank balance daily. Let it pass without a recompute, and the next one will arrive with the same surprise.

Usage-based pricing math is simple here: one input moves, so the output moves with it. The recompute is a small discipline: one invoice, one workload, one price. It does not require a new vendor, a new region, or a new architecture. It requires a number, a choice, and a note of the reason.

The three options are a margin test

Right-size the machine first, because it changes the input. When your machine carries more RAM than the workload needs, lowering it can shrink the line that is about to rise. Additional RAM for Machine presets is listed at $5.00 per gigabyte per month, up to 128 gigabytes. That number turns the new memory price into a dollar amount you can compare against margin, even when you keep the preset.

Move the database when the database drives the machine's memory line. A smaller machine may not be enough. Compare the database's two lines: when the volume line is larger, the database may be worth moving; when the machine memory line is larger, right-sizing may be enough. You may need to dump or migrate the database to a different host, a different region, or a different split between application and data. The decision turns on whether the database line still earns its place in the cost model, not on loyalty to a platform.

Price the increase when the workload is stable and the customer value is clear. Pricing keeps the business honest. The increase can be absorbed into what you charge. A tool, service, or subscription carries the memory line as part of the cost of serving the customer. Slower growth is a deliberate choice. The price should cover the new line, not just the old one.

The recompute fits in five minutes

Keep the checklist short. Each item should be doable in a minute, because the decision is a margin call, not a migration project.

• Open the last invoice and write down the memory, CPU, volume, and snapshot lines.
• Apply the memory increase to the invoice's memory line to get the October change.
• Check the current machine size and note whether a lower RAM option is available.
• For a database, compare the machine memory line against the volume line and note which one is larger.
• Choose the move that protects margin, then write the reason in one line.