Manifesting via EasyPost is Optional
EasyPost is a certified USPS "PC Postage Provider" and with this special partnership, EasyPost is required to daily "manifest" shipment data to USPS. The term manifest in this case basically means we are sending a notice to the USPS electronically for shipping labels that have been purchased. EasyPost does this daily task at 10:30 PM PST (Pacific Standard Time) for all previously unmanifested shipments for all users. Because EasyPost does this automatically each day, users are not required to manually manifest USPS shipments via the API.
If for any reason you feel like you do need to manually manifest USPS shipment you can still do so as long as you do it prior to 10:30 PM PST every day. Manifesting is fairly simple through EasyPost, but in our system, you can review our Manifest Guide here.
Managing manual manifesting
If you do wish to manage your own USPS manifesting there are a couple of things to be aware of when developing your own manifesting solution.
EasyPost daily manifesting is done based on the shipment label_date value.
When you create a USPS label EasyPost assigns a "label_date" (see options) value to the label, which by default is the current date and time. When 10:30 PM PST comes we run a job that looks for all unmanifested labels with label_date that is earlier than the current time. What this means is that you can bypass EasyPost daily manifesting by manually setting label_date to a future date and time. There are actually two options that can be used to manipulate the label_date value.
- label_date (string) - Set the date that will appear on the postage label. Accepts ISO 8601 formatted string including time zone offset. EasyPost stores all dates as UTC time.
- date_advance (numeric) - This option is not publically documented, but you can pass in a number with this option to push the default date out however many days you would like. For Example, if you used `date_advance: 2` as an option it would set the label_date to the current time + 2 days. This can be an easy way to always set your label_date ahead a fixed number of days.
NOTE: You will need to avoid manifesting USPS First Class rates with predefined_package types, "Card", "Letter", and "Flat". These types of First Class USPS shipments will cause the "Unable to create manifest" error as they are not trackable services and therefore are unable to be manifested.