Letter object
A letter.
A unique identifier for the letter, prefixed with ltr_. Use this ID to retrieve, update, or delete the letter.
1 - 99999
"ltr_9a32a8b5a96c880c"
Represents the current status of a letter in the mailing process:
queued
: Awaiting processingready
: Processed and ready for printinginProduction
: Being printed and prepared for mailingmailed
: Handed off to postal service for deliveryissue
: Problem that needs addressingcanceled
: Letter will not be mailed
queued
, ready
, inProduction
, mailed
, issue
, canceled
"queued"
An object containing the sender's information for the letter. It must include:
Either an individual
object, an organization
string, or both.
- If
individual
is provided, it can contain either afullName
string or name components (at minimumfirstName
andlastName
). - If only name components are provided, they will be used in the order specified in our API for addressing.
- If both
fullName
and name components are provided,fullName
will be used for addressing.
An address
object with the sender's complete address details.
This information is used to populate the return address on the letter. Ensure all provided details are accurate to facilitate any potential return mail handling.
Recipient information for the letter. Either individual or organization is required; both can be provided. For accurate NCOA processing, provide name components when available.
Content of the letter.
Indicates the letter's purpose: 'marketing' or 'transactional'. Affects eligibility for USPS promotions and sales tax compliance.
marketing
, transactional
"marketing"
Array of events in the letter's lifecycle.
Represents a lifecycle event for a letter.
The timestamp the resource was created at (UTC).
The timestamp the resource was last modified at (UTC).
Optional client-defined identifier for referencing this letter in external systems. Not used by Posta for processing.
99999
"0013i00002YyVvSAAV"
Specifies the Send Date in ISO 8601 format (YYYY-MM-DD). Time portion, if provided, is ignored.
If omitted:
- SLA begins after the daily cutoff and we auto-assign a date based on our SLA:
- Before cutoff: Earliest production date (e.g., same day if sent 9 am Tuesday).
- After cutoff: Next production date (e.g., next day if sent 11 am Tuesday).
- Non-production day: Next production date.
If specified:
- Must be between current date and 180 days in future.
- If specified date is a production day, value remains as-is.
- If not a production day, next production day is assigned.
Daily cutoff: 10 am ET on production days (Monday - Friday, exluding national holidays)
Note: All letters are cancelable on or before the Send Date's daily cutoff.
Example: 2023-08-15
Optional description for internal reference. Does not affect processing or delievery.
99999
"Compliance notice"
Temporary URL to download the rendered letter PDF. Expires after a set period.
99999
"https://api.posta.co/letters/ltr_9a32a8b5a96c880c/download"
Key-value pairs for personalizing letter content when using handlebars in HTML content.
Represents a variable with a name and optional value for dynamic personalization.
Customization options for letter production and delivery, including:
- Printing preferences (e.g., color, simplex/duplex)
- Mailing preferences (e.g., mail class, extra services)
- Data processing preferences (e.g., CASS, NCOA)
- Other preferences
Defaults apply if not specified. See Option
documentation for details.
Note: Some options may affect pricing or production time.
Human-readable description of any issues encountered with the letter.
99999
"Recipient address could not be validated"
A key-value store for custom metadata.
Limitations:
- Up to 20 metadata key-value pairs
- Key must be no more than 64 characters
- Value must be no more than 512 characters