Convert an MT940 bank statement to CSV

Turn a SWIFT MT940 statement (.sta) into CSV for accounting software or a spreadsheet.

What the parsed statement looks like

bafi splits the message into fields named after their tags, prefixed with F_:

• .Header - the header blocks {1:...}{2:...}
• .Fields - statement-level fields: :20: is .Fields.F_20, :60F: is .Fields.F_60F, ...
• .Transactions - one entry per :61: line, with its :86: details: .F_61, .F_86

The values are the raw field texts; split them in the template (or in Lua).

Sample statement

{1:F01BANKCZPPAXXX0000000000}{2:I940BANKCZPPXXXXN}{4:
:20:STMT-2024-001
:25:CZ6508000000192000145399
:28C:1/1
:60F:C240301EUR1000,00
:61:2403040304C250,00NTRFNONREF
:86:Invoice 2024-17 paid by Alice Smith
:61:2403050305D99,90NTRFNONREF
:86:Office supplies
:62F:C240305EUR1150,10
-}

Template

slice cuts fixed positions out of :61: (date YYMMDD, then C/D), and dateFormat turns the date into DD.MM.YYYY.

Statement,Date,Type,Details
{{- $ref := .Fields.F_20}}
{{- range .Transactions}}
{{$ref}},{{dateFormat (slice .F_61 0 6) "060102" "02.01.2006"}},{{if eq (slice .F_61 10 11) "C"}}credit{{else}}debit{{end}},"{{.F_86}}"
{{- end}}

bafi -i statement.sta -t statement-csv.tmpl

Statement,Date,Type,Details
STMT-2024-001,04.03.2024,credit,"Invoice 2024-17 paid by Alice Smith"
STMT-2024-001,05.03.2024,debit,"Office supplies"

.sta files are recognised by their extension; for other names add -f mt940.

Several statements in one file

Exports such as Multicash put many messages in one file. Pass the separator between messages with -d; bafi then returns a list of statements:

bafi -i multicash.sta -d "-}\r\n" -t '?{{range .}}{{.Fields.F_20}} {{end}}'

\r and \n in -d are turned into real line breaks.

Related: Custom logic with Lua · Template guide