What the ACH company ID is
Every batch of ACH payments names the business that sent it. The name is for people. The company ID is for banks: a 10-character code in the batch header of the ACH file, in a field called Company Identification.
Nacha describes it in two short sentences: it is used to identify the originator, and it is assigned by the originator’s bank.
| Fact | Detail |
|---|---|
| Length | 10 characters |
| Who assigns it | The bank that sends the payments for the business |
| Common form | 1 followed by the 9-digit EIN. For EIN 42-1145552, the ID is 1421145552 |
| Where it sits | Positions 41 to 50 of the batch header, repeated in the batch control |
Banks can assign a different number, and one bank’s guide tells customers not to use a Social Security number or an account number as part of it.
Why you might need one
You pay bills from a business account with a debit block
Banks such as Chase and Wells Fargo offer an ACH debit block or filter for business accounts. It stops every ACH debit except those from company IDs you have approved. It is a strong defense against fraud, but it means a new biller’s first payment is rejected unless you add its ID first. The return can reach the biller as R29.
To add a biller:
- Ask the biller for its ACH company ID. Some billers use more than one.
- Give the ID to your bank, or add it in your online banking.
- Ask the biller to try again after the ID is approved.
You send ACH files
Your bank gives you the company ID to put in each batch. The same value often goes in the Immediate Origin field of the file header. If you use the NACHA file generator, enter both exactly as your bank gave them.
A customer asks for yours
Customers with debit filters will ask for your company ID before your first debit. Have it ready. If you collect through a payment processor, ask the processor which ID your payments carry.
Why there is no official lookup
A company ID is chosen by a business’s bank, not issued from a central registry. Nacha does keep some registries, such as the list of registered third-party senders, but they sit in a portal for financial institutions and are not open to the public. The Federal Reserve’s public directory covers bank routing numbers, not company IDs.
So a search for “ACH company ID lookup” leads to unofficial lists. Treat them with care. A wrong ID in your debit filter blocks the payment you wanted, and a guessed one can let through a payment you did not.
Company IDs that tax agencies publish themselves
Some government agencies publish the company IDs they use, so that customers with a debit block can approve them. Always copy the ID from the agency’s own page.
| Agency | What the payment is for | The agency’s page |
|---|---|---|
| Massachusetts Department of Revenue (DOR) | Electronic payments made to the department | DOR page on ACH debit blocks |
| Michigan Department of Treasury | Business tax payments made by EFT debit | Treasury page on EFT debit payments |
This table is not a directory. It only lists agencies that publish their own IDs. We opened both pages on October 2, 2026. We do not print the IDs here, because an ID that has changed would block your tax payment. Michigan lists more than one ID. Which one you need depends on the system you pay through.
For any other biller, there are two ways to get the ID:
- Look at a payment the biller has already taken. The company ID travels with every ACH payment. Your online banking may show it in the payment details. If it does not, ask your bank for the ACH detail of that payment.
- Ask the biller. Billers hand these out because they know customers need them.
Related terms
| Term | Meaning |
|---|---|
| Originator | The business that sends the ACH payment |
| ODFI | Originating Depository Financial Institution: the originator’s bank |
| RDFI | Receiving Depository Financial Institution: the bank of the person or business being paid or debited |
| Immediate origin | Who sent the file. In the file header |
| Immediate destination | The bank the file is sent to. In the file header |
Common mistakes
- Confusing it with a routing number. A routing number has 9 digits and identifies a bank. A company ID has 10 characters and identifies a business.
- Using an ID from an unofficial list. Ask the biller.
- Forgetting that processors use their own ID. If you pay or collect through a processor, the ID on the payment is usually the processor’s.
- Changing banks without telling customers. A new bank can mean a new company ID. Customers with debit filters need the new one before your next debit.