X12 File Naming Standards Quick Guide
This guide should only be used by trading partners who submit batch transactions in the ANSI national standard X12 format.
Standardized file naming conventions are required for X12 file uploads and will be used for all response files.
File Naming Standard Components
Below are the required standardized file naming convention components that must be used to name all files before they are uploaded.
File names are not case sensitive. File names must be structured as follows:
<TPID>-<TransactionType>-<yyyymmddhhmmssSSS>-<1of1>.<File Extension>
NOTE: <Examples> shown above include brackets that indicate specific configurable fields. Do not include < > in actual file names.
- TPID: Trading Partner ID is the same ID that is used for the MOVEit SFTP server. Upon submission, x12s must include ‘tp’ in front of the ID number (e.g., tp12345).
- Transaction Type: The Transaction Type is the number for the transaction Trading Partners are submitting (i.e., 270, 276, 837P, 837I, 837D).
- Time Stamp (yyyymmddhhmmssSSS): The Time Stamp is the time Trading Partners are generating the file down to the millisecond. Military time (24-hour) and Mountain Time (MT) are required. The time stamp must include the four-digit year, two-digit month, two-digit day, two-digit hour, two-digit minutes, two-digit seconds, and three-digit millisecond (e.g., 202509261322435).
- 1of1: The “1of1” component describes that one out of one file is being submitted. The component “1of1” is static and does not change. Trading Partners can not enter 1of2, 1of3 or any text other than 1of1 within the fourth segment of the file name to meet requirements. This field is not customizable, and unique or specific values are not allowed.
Note: 1of 2 or 1of 3, etc. are not accepted. Files are not processed based on this sequence. - File Type (File Extension): The File Type indicates the format of the file. Trading Partners should only name outbound files with the extension .x12, but Trading Partners may receive inbound files with different extensions (e.g., .html, .x12, .txt).
Below are examples for each transaction that Trading Partners may submit:
| Transaction | File Name Example |
|---|---|
| 270 | tp12345-270-yyyymmddhhmmssSSS-1of1.x12 |
| 276 | tp12345-276-yyyymmddhhmmssSSS-1of1.x12 |
| 837P | tp12345-837P-yyyymmddhhmmssSSS-1of1.x12 |
| 837I | tp12345-837I-yyyymmddhhmmssSSS-1of1.x12 |
| 837D | tp12345-837D-yyyymmddhhmmssSSS-1of1.x12 |
Below are the constraints around file naming conventions:
| Constraint | Details |
|---|---|
| Max File Name Length | 255 Characters |
| Hyphens (-) | Only allowed between components (e.g., tp2345-270) |
| Special Characters | No special characters are allowed other than hyphens (-) and periods (.). |
Response and Acknowledgement Files
File Name Configuration: Trading Partners should configure their system to allow for file naming changes to response and acknowledgement files such as 999, 271, 277, 835, 834 and 820.
Tracking ID: The Tracking ID is created by the source system once a file is retrieved by the source system. It is a unique system-generated value containing ten alphanumeric characters (i.e., 0-9), preceded by a “M” or “E”, and will be included in the Response and Acknowledgement or the Report files received by the Trading Partners. Underscores will be used to separate sub-elements, for example, “1of1_999” or “270_M123456”.
Examples include:
Acknowledgement Files
- tp12345-270_TrackingID-yyyymmddhhmmssSSS-1of1_999.x12
- tp12345-270_TrackingID-yyyymmddhhmmssSSS-1of1_TA1.x12
- tp12345-270_TrackingID-yyyymmddhhmmssSSS-1of1_rpt.html
Response Files
- tp12345-271_TrackingID-yyyymmddhhmmssSSS-1of1.x12
- tp12345-277_TrackingID-yyyymmddhhmmssSSS-1of1.x12
- tp12345-820_TrackingID-yyyymmddhhmmssSSS-1of1.x12
- tp12345-834_TrackingID-yyyymmddhhmmssSSS-1of1.x12
- tp12345-835_TrackingID-yyyymmddhhmmssSSS-1of1.x12
- tp12345-ENCR_TrackingID-yyyymmddhhmmssSSS-1of1_rsp.txt
- tp12345-ENCR_TrackingID-yyyymmddhhmmssSSS-1of1_rpt.txt
Contact the Provider Services Call Center with any questions.