What extra information does a VAT invoice need?

Core full VAT invoice details

HMRC's VAT record-keeping guidance says a full VAT invoice should include a sequential number based on one or more series that uniquely identifies the document, the time of supply, the date of issue, the supplier's name, address and VAT registration number, the customer's name and address, and a description sufficient to identify the goods or services.

For each description, it should also show the quantity of goods or extent of the services, the VAT rate and the amount payable excluding VAT. The invoice should show the relevant totals, the total VAT charged in sterling and the unit price.

Source: HMRC — Record keeping (VAT Notice 700/21).

Supply date and invoice date are not the same idea

The time of supply matters for VAT. Where that differs from the date the invoice is issued, keeping the supply date and invoice date as separate fields prevents one important date from being hidden inside the other.

Keep a copy

HMRC's guidance says VAT invoices you issue form part of your business records and that you must keep a copy of every VAT invoice you issue. That is one reason Klamic treats a finalised invoice as a historical document rather than a file that changes whenever you edit your business profile later.

Know when straightforward invoicing stops being enough

Klamic V1 is designed around ordinary small-business and service invoices. If a transaction uses a special VAT scheme or requires specialist wording, check the relevant HMRC guidance or take professional advice rather than trying to force the transaction into a standard template.

How Klamic handles ordinary VAT invoices

When a business profile is marked as VAT registered, Klamic stores the VAT number, lets invoice lines carry VAT rates, calculates VAT separately and preserves the invoice details when the invoice is finalised.