What types of mailings must have coding done within 90 days before mailing?

The requirement that coding must be completed within 90 days before mailing specifically applies to all carrier route mailings. This is because carrier route mailings are designed to target specific postal routes and require an up-to-date coding system to ensure accurate delivery and efficient processing by the postal service.

Using the most accurate and recent data for coding is crucial in managing the flow of mail and addressing changes, as the carrier routes can frequently change based on various factors like population shifts or postal service updates. By adhering to this 90-day coding rule, businesses can enhance their mail delivery efficacy and ensure that their mail reaches the intended recipients in a timely manner.

In contrast, other mailing types may not have a specific requirement to refresh coding within such a short timeframe, making the coding mandate for carrier routes distinct and significant within the context of mailing practices.