Xero prepayment journals for a tour operator, validated 107/107 against the bookkeeperXero prepayment journals for a tour operator, validated 107/107 against the bookkeeper

A tour operator pays accommodation suppliers in advance. Each month the bookkeeper typed references and descriptions onto supplier bills by hand and split VAT across several rates, then moved prepaid costs to expense according to each tour's arrival month.

What was broken

Month-end ran on hand-typing. The bookkeeper keyed references and descriptions onto supplier bills, split VAT across several rates, and moved prepaid accommodation costs to expense according to each tour's arrival month.

What it cost

• Bills from 59 accommodation suppliers, each with its own layout, coded by hand every month.
• VAT split by hand across the Irish 9%, 13.5% and 23% rates and the UK 20% rate.
• A month-end journal that depended on one person getting every arrival month right.

The brief

Automate the coding and the month-end prepayment journals without ever posting something the bookkeeper would not have posted. A wrong journal in a client's ledger is worse than no automation.

• 59 suppliers with different invoice layouts and multiple VAT rates (Irish and UK).
• Nothing posts without the bookkeeper: journals stay in draft until approved.
• Releases must be impossible to run twice for the same month.

• Architect and builder, delivered through M.A. Whately & Co.
• The bookkeeper stays the approver: journals stay in draft until approved.
• Acceptance was the bookkeeper's own manual entries, compared field by field before go-live.

1. 00

   Before

   References, descriptions, VAT splits and the prepayment journal all done by hand.

2. 01

   Rehearsal

   The full flow rehearsed on the Xero demo company.

3. 02

   Comparison

   Matched the bookkeeper's own entries 107 of 107 on the comparison set.

4. 03

   Dry run

   271 bills scanned on the live ledger with writes disabled. Nothing changed.

5. 04

   16 Oct 2026

   Live. The first production draft journal generated on schedule.

6. 100

   25 Oct 2026

   10 of 10 daily production runs green, every morning on GitHub Actions.

What was built

• Layout-free bill reading that validates its own arithmetic against the VAT table on the bill before it trusts a figure.
• A Xero sync that writes references and descriptions onto matching unpaid bills, and maintains a running draft journal moving prepayments to expense by arrival month.
• A review list for anything uncertain, and an email to the bookkeeper whenever a run fails.
• A month-end release with a guard against double release, scheduled on GitHub Actions every morning with the ledger credentials encrypted in secrets.

• Journals stay in draft until the bookkeeper approves them.
• The reader validates the arithmetic against the VAT table on the bill before it trusts a figure.
• A guard makes a month-end release impossible to run twice for the same month.
• Uncertain cases go to a review list instead of a guess, and the bookkeeper is emailed whenever a run fails.
• Ledger credentials AES-256 encrypted in repository secrets, with single-copy token discipline.

How it was tested

The system was rehearsed on the Xero demo company, compared field by field against the bookkeeper's manual work, then dry-run on the live ledger with writes disabled. Only then did it go live. Uncertain cases go to a review list instead of a guess.

• The repository, the schedule and the encrypted credentials.
• A runbook and a rehearsal log the bookkeeper and the firm can follow.

• Python 3.12
• Xero Accounting API (OAuth2)
• GitHub Actions
• pypdf

1. Upwork review5 out of 5 stars

   Adrian is a great professional! He finished the job perfectly with a very detailed instructions on how to use it and is always available to help!