--- source: https://carbone.io/examples/nacha-ach-file/ title: "NACHA File Generator: Create ACH Files from JSON | Carbone" description: "Create NACHA files from your payroll or supplier payment data with the Carbone API: a TXT template writes the ACH file, entry hash and totals included." generated_at: "2026-11-12" --- # NACHA File Generator: Create ACH Files from JSON Turn payroll or supplier payments from your software into a valid ACH file [![NACHA File Generator: Create ACH Files from JSON](/examples/nacha-ach-file/thumb-result.webp)](/examples/nacha-ach-file/result.txt) [Download Template](/examples/nacha-ach-file/template.txt) [Download data sample](/examples/nacha-ach-file/data.json) - Template type document txt simple - Carbone min. v5.4.3+ - Features loop aggregator padding condition - Target finance payroll bank ## Generate NACHA files from your software Payroll platforms, accounting software and fintechs pay through US banks with NACHA files, also called ACH files: text files of 94-character records in blocks of 10 lines, in the format set by [Nacha](https://www.nacha.org/). Your application sends its payments to the Carbone API as JSON and gets back the ACH file to upload to the bank. In this example, Acme Corporation pays five employees. ## NACHA file layout The first character of each line is its record code: | Record | Code | Content | | --- | --- | --- | | File Header | `1` | Who sends the file, to which bank, and when | | Batch Header | `5` | The company, the payment type and the pay date | | Entry Detail | `6` | One line per employee: bank, account, amount in cents, name | | Batch Control | `8` | Batch totals: payment count, entry hash (a checksum), amount paid | | File Control | `9` | The same totals for the file, plus the block count | | Filler lines | `9` | Lines of 94 nines that complete the last block | ## NACHA file example ### Template ```text {o.timezone=America/New_York}101 {d.bank.routing}{d.company.id}{d.file.createdAt:formatD('YYMMDDHHmm')}A094101{d.bank.name:upperCase:padr(23)}{d.company.name:upperCase:padr(23)}{d.file.reference:padr(8)} 5220{d.company.name:upperCase:substr(0, 16):padr(16)} {d.company.id}PPD{d.batch.description:upperCase:padr(10)}{d.batch.effectiveDate:formatD('MMM DD'):upperCase}{d.batch.effectiveDate:formatD('YYMMDD')} 1{d.bank.routing:substr(0, 8)}0000001 {d.entries[i]}6{d.entries[i].accountType:ifEQ(savings):show(32):elseShow(22)}{d.entries[i].routing}{d.entries[i].account:padr(17)}{d.entries[i].amount:mul(100):round(0):padl(10, '0')}{d.entries[i].id:padr(15)}{d.entries[i].name:unaccent:upperCase:substr(0, 22):padr(22)} 0{d.bank.routing:substr(0, 8)}{d.entries[i].id:cumCount:padl(7, '0')} {d.entries[i+1]}8220{d.entries:len:padl(6, '0')}{d.entries[].routing:substr(0, 8):aggSum:mod(10000000000):padl(10, '0')}000000000000{d.entries[].amount:mul(100):round(0):aggSum:padl(12, '0')}{d.company.id} {d.bank.routing:substr(0, 8)}0000001 9000001{d.entries:len:add(4):div(10):ceil:padl(6, '0')}{d.entries:len:padl(8, '0')}{d.entries[].routing:substr(0, 8):aggSum:mod(10000000000):padl(10, '0')}000000000000{d.entries[].amount:mul(100):round(0):aggSum:padl(12, '0'):padr(51)}{d.entries:len:add(3):mod(10):ifLT(9):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(8):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(7):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(6):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(5):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(4):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(3):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(2):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd}{d.entries:len:add(3):mod(10):ifLT(1):showBegin} 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999{d.entries:showEnd} ``` ### JSON data ```json { "file": { "createdAt": "2026-11-12T14:05:00-05:00", "reference": "PR261113" }, "bank": { "name": "Contoso Bank", "routing": "041108291" }, "company": { "name": "Acme Corporation", "id": "1470259836" }, "batch": { "description": "Payroll", "effectiveDate": "2026-11-13" }, "entries": [ { "id": "EMP00417", "name": "Olivia Bennett", "accountType": "checking", "routing": "071403623", "account": "3820174956", "amount": 2845.16 }, { "id": "EMP00422", "name": "José Ramírez", "accountType": "savings", "routing": "263071575", "account": "000738291054", "amount": 1932.5 }, { "id": "EMP00431", "name": "Hannah Kowalski", "accountType": "checking", "routing": "322374184", "account": "59302817", "amount": 3410 }, { "id": "EMP00438", "name": "Marcus Thompson", "accountType": "checking", "routing": "062109512", "account": "1100493827", "amount": 2276.84 }, { "id": "EMP00445", "name": "Priya Raghunathan-Sullivan", "accountType": "savings", "routing": "113017346", "account": "7730015529", "amount": 4105.37 } ] } ``` ### Generated ACH file ```text 101 04110829114702598362611121405A094101CONTOSO BANK ACME CORPORATION PR261113 5220ACME CORPORATION 1470259836PPDPAYROLL NOV 13261113 1041108290000001 6220714036233820174956 0000284516EMP00417 OLIVIA BENNETT 0041108290000001 632263071575000738291054 0000193250EMP00422 JOSE RAMIREZ 0041108290000002 62232237418459302817 0000341000EMP00431 HANNAH KOWALSKI 0041108290000003 6220621095121100493827 0000227684EMP00438 MARCUS THOMPSON 0041108290000004 6321130173467730015529 0000410537EMP00445 PRIYA RAGHUNATHAN-SULL 0041108290000005 822000000500831976220000000000000000014569871470259836 041108290000001 9000001000001000000050083197622000000000000000001456987 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999 ``` ## How to create a NACHA file ### 1\. Write one line per record Type the fixed values as they are, like the record size `094`, and build the other fields with the [fixed-width formatters](/documentation/design/template-formats/txt.md#fixed-width-files): `{d.company.name:upperCase:substr(0, 16):padr(16)}` fits ACME CORPORATION into its 16 characters. `{o.timezone=America/New_York}` prints the file time in New York time. ### 2\. Add one Entry Detail per payment The Entry Detail line is a [loop](/documentation/design/template-formats/txt.md#loops) on `d.entries`. On Olivia Bennett's line: - `22` pays a checking account, `32` a savings account: `:ifEQ(savings):show(32):elseShow(22)`. - `071403623` is the routing number of her bank. - `:mul(100):round(0):padl(10, '0')` turns 2,845.16 into `0000284516`. - `{d.entries[i].id:cumCount:padl(7, '0')}` ends the trace number with her position: `041108290000001`. ### 3\. Compute the control totals The bank recomputes these totals and rejects a file that does not match. Carbone computes them from the payments with [aggregators](/documentation/design/computation/aggregation.md): - **Entry count**: `{d.entries:len:padl(6, '0')}` prints `000005`. - **Entry hash**: `{d.entries[].routing:substr(0, 8):aggSum:mod(10000000000):padl(10, '0')}` adds the first 8 digits of each routing number and keeps the last 10 digits: `0083197622`. - **Total credits**: `{d.entries[].amount:mul(100):round(0):aggSum:padl(12, '0')}` prints `000001456987`, or 14,569.87. ### 4\. Fill the last block with 9s The line count must be a multiple of 10. `{d.entries:len:add(4):div(10):ceil}` gives the block count, and the template ends with nine lines of `9`. Each one is a [conditional block](/documentation/design/conditions/conditional-blocks.md#showbegin-showend) on `{d.entries:len:add(3):mod(10)}`, the position of the File Control in its block, so only the missing lines are kept: one with 5 payments, nine with 7. The ACH file keeps the CRLF line endings of the template. ## Related Examples [![Bank statement (simple)](/examples/bank-statement-simple/thumb-result.webp)](/examples/bank-statement-simple/index.md) [![Create EDIFACT Invoices from JSON with an EDI API](/examples/edifact-invoice/thumb-result.webp)](/examples/edifact-invoice/index.md) ## Trusted by 800+ paid customers in 40+ countries Industries: Finance, Healthcare, Insurance, Legal, Public, Retail, Energy, Software, Telecom. Customers include Dior, Thales, Younited, Danfoss, CMA CGM, Illumina, KparK, Scalingo, French Ministry of the Armed Forces, BMW, Telus, Bestseller, Flagship Biosciences, Insly, Ninox, Sodexo. ## Related topics - [Transport ticket](/examples/ticket/index.md) - [Summary](/examples/summary/index.md) - [Stock inventory spreadsheet](/examples/stock-inventory-spreadsheet/index.md) - [Store Inventory](/examples/shoes/index.md) - [Sensor readings](/examples/sensor-readings/index.md) - [Real estate property document](/examples/real-estate-property-description/index.md)