Skip to content
Fetching contributors…
Cannot retrieve contributors at this time
79 lines (59 sloc) 2.37 KB


Build Status

ach is a Ruby helper for builder ACH files. In particular, it helps with field order and alignment, and adds padding lines to end of file.

This library has only been used in one production application and for very limited purposes. Please test thoroughly before using in a production environment.

See ACH::Builder for a similar Perl library


You should consult a copy of the ACH Rules for details on individual fields. You can probably obtain a copy from your bank.

require 'ach'

# Create ACH file
ach =
trace_number = 0

# File Header
fh = ach.header
fh.immediate_destination = '000000000'
fh.immediate_destination_name = 'BANK NAME'
fh.immediate_origin = '000000000'
fh.immediate_origin_name = 'BANK NAME'

# Batch
batch =
bh = batch.header
bh.company_name = 'Company Name'
bh.company_identification = '123456789' # Use 10 characters if you're not using an EIN
bh.standard_entry_class_code = 'PPD'
bh.company_entry_description = 'DESCRIPTION'
bh.company_descriptive_date =
bh.effective_entry_date =
bh.originating_dfi_identification = '00000000'
ach.batches << batch

# Detail Entry
ed =
ed.transaction_code = ACH::CHECKING_CREDIT
ed.routing_number = '000000000'
ed.account_number = '00000000000'
ed.amount = 100 # In cents
ed.individual_id_number = 'Employee Name'
ed.individual_name = 'Employee Name'
ed.originating_dfi_identification = '00000000'
batch.entries << ed
# ... Additional detail entries, possibly including *offsetting entry*, if needed.

# Insert trace numbers
batch.entries.each.with_index(1) { |entry, index| entry.trace_number = index }

File.write('ach.txt', ach.to_s)

# Parse an ACH file
ach ='examples/ach/fixtures/return_noc.txt'))
=> "C05992222220280489      1211403932                                          1211"

Note: When adding an amount to your ach file, it needs to be in cents. So you'll want to multiply any dollar amounts by 100


Copyright (c) 2008-2009 Jared E Morgan, released under the MIT license

Something went wrong with that request. Please try again.