How do I create - or read - an ACH (NACHA) File?

If you want to create an ACH file or read an existing ACH file, here's the information you need to know.

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A quick and easy way to create an ACH file is to use ACH Universal^™ a client-side solution that you can download at your work station.
These links can help you get started creating files:

For QuickBooks users - QuickBooks

QuickBooks online - QuickBooks Online

If you're using Excel or CSV files (and other accounting packages) - Excel, csv files

For SQL users - SQL Insertion

If you're interested in learning the details of an ACH file - or if you want to create your own ACH file without a tool - here's the nitty gritty.

See ACH File Format specifications for Nacha PPD and CCD.

Overview

The ACH file is a fixed-width ASCII text file that is 94 characters in width, in an enveloped/nested format.

Below is a basic layout that might be used for:
--Customer Collections
--Employee Direct Deposit
--Vendor Payments

The number in the first position of each record defines what type of record it is:
1 - File Header
5 - Batch Header
6 - Transactions
7 - Addenda record (optional)
8 - Batch Footer
9 - File Footer

Sample ACH File Format

 

File Headers and Footers - Overview

The file header and footer are marked in yellow:
1 - File Header
9 - File Footer

File Header (1 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	1	Constant
2-3	2	Priority Code	01	Constant
4-13	10	Immediate Destination	bNNNNNNNNNN	Typically your bank's 9 digit ABA Routing number, preceding with a blank space. Determined by your bank.
14-23	10	Immediate Origin	Numeric	Typically a "1" + your Federal ID number. Determined by your bank.
24-29	6	File Creation Date	YYMMDD	Must be in YYMMDD format
30-33	4	File Creation Time	HHMM	Must be in HHMM format (use 24 hour format)
34-34	1	File ID Modifier	Alphanumeric	Alphanumeric field, upper-case A-Z and 0-9 allowed. Start with A and increment for each file created during the calendar day.
35-37	3	Record Size	094	Constant
38-39	2	Blocking Factor	10	Constant
40-40	1	Format Code	1	Constant
41-63	23	Immediate Destination Name	Alphanumeric	Enter your bank's name
64-86	23	Immediate Origin Name	Alphanumeric	Enter your company's name
87-94	8	Reference Code	Blank	8 blank spaces - constant

File Footer (9 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	9	Constant
2-7	6	Batch Count	Numeric	Number of batches in file
8-13	6	Block Count	Numeric	Number of blocks in file (10 records = 1 block)
14-21	8	Entry/Addenda Count	Numeric	Number of detail entry (transactions) and addenda records within the file.
22-31	10	Entry Hash	Numeric	Sum of the receiving DFI ID (first 8 digits of the other party's ABA routing number) for each entry/transaction within the file. If the sum exceeds 10 places, use the rightmost 10 digits.
32-43	12	Total Debit Entry Dollar Amount	Numeric	Total debits for the file. No decimal.
44-55	12	Total Credit Entry Dollar Amount	Numeric	Total credits for the file. No decimal.
56-94	39	Reserved	Blank	Constant

Note: Padding record - in gray:
ACH files need to be created in multiples of 10 records. In this sample, there are 9 records including the file header and footer noted in yellow. In this case, we needed to add one additional padding record (99999...) to make the file contain a multiple of 10 records.
Therefore, an ACH may have anywhere from no padding (99999...) records up to 9 records.

Batch Header and Footer - Overview

There are two batches in this sample, with the headers and footers marked in in yellow:
5 - Batch Header
8 - Batch Footer

Batch Header (5 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	5	Constant
2-4	3	Service Class Code	200 220 225	Represents whether the batch contains: 200 Both Debits and Credits, mixed 220 Credits 225 Debits
5-20	16	Company Name	Alphanumeric	Your company name. Often the same as the Immediate Origin Name in the file header. PRINTED - This value will appear on the other party's bank statement
21-40	20	Company Discretionary Data	Alphanumeric	Optional. May be instructed by your bank. Otherwise (typically), leave blank
41-50	10	Company Identification	Numeric	Typically a "1" + your Federal ID number. Determined by your bank. Often the same as the Immediate Origin ID in the file header. No hyphen, numbers only.
51-53	3	Standard Entry Class Code (SEC)	PPD, CCD	3 letter mnemonic which identifies the batch and its' layout. PPD - used if the other party is an individual (ie. payroll) CCD - used if the other party is a corporate account (ie. vendor payments and customer collections). Other values (not part of this layout/sample) include ARC, BOC, CTX, IAT, TEL and WEB.
54-63	10	Company Entry Description	Alphanumeric	A description as to the general nature of the transactions to help the other parties identify the purpose. Examples: Payroll, Payables, etc... PRINTED - This value will appear on the other party's bank statement
64-69	6	Company Descriptive Date	Alphanumeric, often YYMMDD	Optional. Descriptive date - often in YYMMDD with the same value as the effective date. Useful in recurring transaction scenarios, such as payroll. PRINTED - This value may appear on the other party's bank statement
70-75	6	Effective Entry Date	YYMMDD	Effective / transaction date. Date the other party is to be debited or credited.
76-78	3	Reserved	Blank	Julian Settlement Date - left blank. Will be filled in by your bank.
79-79	1	Originator Status Code	1	Constant
80-87	8	Originating DFI ID	Numeric	Enter the first 8 digits of your ABA routing number
88-94	7	Batch Number	Numeric	Start with 00000001 and increment by 1 for each batch.

Batch Footer (8 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	8	Constant
2-4	3	Service Class Code	200 220 225	Represents whether the batch contains: 200 Both Debits and Credits, mixed 220 Credits 225 Debits Must match the entry in the batch header.
5-10	6	Entry/Addenda Count	Numeric	Number of detail entry (transactions) and addenda records within the batch.
11-20	10	Entry Hash	Numeric	Sum of the receiving DFI ID (first 8 digits of the other party's ABA routing number) for each entry/transaction within the batch. If the sum exceeds 10 places, use the rightmost 10 digits.
21-32	12	Total Debit Entry Dollar Amount	Numeric	Total debits for the batch. No decimal.
33-44	12	Total Credit Entry Dollar Amount	Numeric	Total credit for the batch. No decimal.
45-54	10	Company Identification	Numeric	Typically a "1" + your Federal ID number. Determined by your bank. Must match the entry in the batch header.
55-73	19	Message Authentication Code	Blank	Blank
74-79	6	Reserved	Blank	Blank
80-87	8	Originating DFI ID	Numeric	Enter the first 8 digits of your ABA routing number Must match the entry in the batch header.
88-94	7	Batch Number	Numeric	Start with 00000001 and increment by 1 for each batch. Must match the entry in the batch header.

 

 

Transactions

There are three transactions (Entry Detail) records in this sample marked in in yellow:
6 - Transactions (Entry Detail)

Entry Detail / Transaction (6 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	6	Constant
2-3	2	Transaction Code	22 32 27 37 etc...	For credit (ie. payroll, vendor payments) transactions: 22 Checking account 32 Savings account For debit (ie. collections from a customers) transactions: 27 Checking account 37 Savings account For pre-notes: 23/28 for checking credit/debit 33/38 for savings debit/credit See ACH Rules for additional codes.
4-11	8	Receiving DFI ID	Numeric	First 8 digits of the other party's ABA routing number
12-12	1	Check Digit	Numeric	Last digit of the other party's ABA routing number
13-29	17	DFI Account Number	Alphanumeric	Other party's account number. Note: This is an alphanumeric field and should be left justified.
30-39	10	Amount	Numeric	Transaction amount. No decimal.
40-54	15	Identification Number	Alphanumeric	Optional. Helps the receiver (other party) identify themselves within your system, should they need to contact you. Typically their account number. PRINTED - This value may appear on the other party's bank statement
55-76	22	Receiving Company Name	Alphanumeric	The other party's company name (in CCD) - or if a consumer transaction (in PPC) such as payroll, the individual's name.
77-78	2	Discretionary Data	Alphanumeric	Typically blank, unless instructed otherwise by your bank.
79-79	1	Addenda Record Indicator	0 or 1	0 - No addenda following 1 - Addenda following
80-94	15	Trace Number	Numeric	The first 8 digits of your Originating DFI number, followed by the entry detail sequence number,

Addenda Records

Addenda Record - optional (7 record)
Positions	Length	Name	Contents	Description
1-1	1	Record Type Code	7	Constant
2-3	2	Addenda Type Code	05	Constant. Only valid value for CCD and PPD originations. Other SEC codes can contain other values.
4-83	80	Payment Related Information	Alphanumeric	Invoice or other remittance information specific to the entry detail / transaction. PRINTED - This value may appear on the other party's bank statement Note: Do NOT rely on the other party obtaining this information. Most bank's require an election for additional services to receive this.
84-87	4	Addenda Sequence Number	0001	As PPD and CCD codes only support 1 addenda record, this will always be 0001.
88-94	7	Entry Detail Sequence Number	Numeric	This 7 digit field contains the last 7 digits of the related (preceding) entry detail / transaction record's trace number.

 

 

Notes:

The screen shots on this page contain text describing fields for PPD and CCD transactions, using common-use terms and descriptions, along with fictitious routing & account numbers and typical use examples/formats. NACHA field names and rules follow each illustration.

Numeric fields - Right justified, zero padded.
Alphanumeric fields - Left justified, blank padded.

 

Offset Records - Balanced files
Some banks will require a balanced file - where the debits and credits need to be equal. To do this, you will need to add an offset record to balance the file. Therefore, if the file has $1,000 in debits and $10,00 in credits, you will need to create a debit offset record of $9,000.

Advanced note: The offsets are calculated by effective date. Therefore, if a file has transactions with multiple effective dates, you will need to group and total the transactions by date - and then create multiple offset transactions - one for each effective date.

Pre-note records
Pre-notes are transactions used to confirm the other party's account. They are $0.00 transactions and can be either debits or credits. It is important to enable the user/system to designate whether they want a debit or credit pre-note - as this should be the same logic as the 'live' transactions will be in the future.
For example, if you want to test the bank account of a new client, you will want to debit pre-note. The reason being, if you use a credit pre-note, and the client has a debit block on their account - the credit pre-note will be successful, however the 'live' transaction might fail.



Encryption
Remember to encrypt all account numbers for data at rest.

Batching Rules
An ACH file has one file header and one file footer, and contains at least one batch.
The batches each have a header and footer. Within each batch are the transactions.
While there can only be one file header and footer, there is no limit to the number of batches or transactions (#1).

Legal Notice
This information is intended to be an abridged guide with commentary - and is not meant as a substitute for the official Nacha ACH Rules and Regulations publication. For an official copy of the ACH Rules and Regulations, please visit https://www.nacha.org/rules

If you are creating ACH files outside of Treasury Software's ACH Universal and need to troubleshoot the file creation process, we recommend that you import the same data into ACH Universal and compare your results.
For rules clarification and explanation, please contact your bank, NACHA or a regional payment association directly.

Footnotes:
1 - There is no limit to the number of transactions, but with certain ACH SEC codes not covered here (ie CTX), there is a limit to 9,999 records.