Khosmos Invoice Compliance Checker for UK Sole Traders

UK sole traders and small contractors face a quiet but real problem: an invoice that misses a required field or applies the wrong VAT rate can trigger client payment delays, disputes, or HMRC compliance headaches. Most freelancers are not accountants, and the rules around VAT numbers, correct tax rates, and compliant payment terms are easy to get wrong. Khosmos Invoice Compliance Checker addresses this by validating an invoice against HMRC requirements before it is sent, flagging missing VAT numbers, incorrect tax rates, and non-compliant payment terms. The solution is a pre-send compliance layer: the freelancer drafts or imports an invoice, the checker runs a rules pass against HMRC formatting and VAT requirements, and returns a clear pass or a list of specific fixes. An MVP could be a lightweight web tool that accepts a manual entry or a PDF/CSV import, runs the compliance ruleset, and returns a checklist with plain-English explanations of each flag. Revenue would follow a low-cost SaaS subscription aimed at individual sole traders, with the option of a per-invoice check for very light users. Go-to-market centers on the exact communities already asking these questions on YouTube around UK VAT and freelance invoicing, plus content that ranks for the specific compliance mistakes freelancers make. Growth loops come from freelancers sharing compliant invoice templates, referrals within contractor networks, and accountant partnerships who recommend the tool to their sole-trader clients. The named direct competitor is Khosmos itself, which sets both a validation and a pricing benchmark for this space.