Spreadsheets can just about handle a handful of self-billed invoices, but they don’t enforce sequential numbering, apply the reverse charge, keep supplier VAT status current, or produce an audit trail. Dedicated self-billing software does all of that automatically and scales to hundreds of suppliers.
Key points
- Spreadsheets don’t enforce unique sequential numbering — a VAT requirement.
- Software applies VAT and the CIS reverse charge automatically per supplier.
- Software keeps agreements, VAT status and copies for the audit trail.
- At volume, software replaces manual re-keying and error-checking.
Where spreadsheets fall short
A spreadsheet won’t stop you duplicating an invoice number, won’t know whether a supplier is VAT-registered today, and won’t apply the reverse charge or a CIS deduction correctly. Every formula is a chance for a silent error on a VAT document.
What software adds
Dedicated software assigns numbers in an unbroken sequence, applies the right VAT treatment from each supplier’s status, calculates reverse charge and CIS deductions, emails copies, and keeps everything for a VAT inspection.
When a spreadsheet is enough
For a one-off or a couple of suppliers with simple standard-rated supplies, a spreadsheet may suffice. The moment you have volume, reverse charge or changing VAT status, software pays for itself.
This is general information, not tax advice — confirm your own position with your accountant or HMRC.