Chat-based invoice drafting
Start an invoice by sending the job details in plain English. WOPA turns the message into a draft and asks for missing information when needed.
WOPA
WOPA is a WhatsApp-based invoicing tool for UK tradespeople that creates PDF invoices, emails customers, and chases unpaid bills from chat. Live beta, free for 3 invoices a month.
Overview
WOPA is a WhatsApp-first invoicing tool for UK tradespeople. It lets you create invoice PDFs, email customers, and follow up on unpaid invoices from a WhatsApp chat instead of a separate desktop app or spreadsheet.
The workflow is built around a short chat: send the job details, review a draft, and approve the invoice before it is emailed. WOPA also tracks payment status and can run polite reminders on a schedule, which makes it useful for sole traders and small businesses that want to handle invoicing where the job conversation already happens.
Core features
Preview and approval step
Review the customer, amount, due date, and bank details before anything is sent. The invoice only goes out after you confirm it.
Email delivery of PDF invoices
Send a professional PDF invoice by email from WhatsApp. WOPA handles the invoice email while keeping the conversation in chat.
Automated payment chasing
Keep unpaid invoices moving with reminders at 7, 14, and 28 days. You can pause, stop, or let reminders run until payment is recorded.
Invoice status tracking
Track whether an invoice is paid, outstanding, or overdue from the chat flow. You can also ask who has not paid and mark invoices as paid in WhatsApp.
UK invoice field support
Supports standard VAT, reverse-charge VAT for construction, and CIS deductions for subcontractors, with fields designed for UK trade invoices.
Common use cases
Invoice from the job chat
For electricians, plumbers, builders, and other tradespeople who want to raise an invoice while the job details are still fresh, without opening a separate invoicing app.
Send professional invoices by email
For users who want a customer-facing PDF invoice sent by email, while they manage the process from WhatsApp and confirm the draft before sending.
Chase unpaid invoices
For businesses that need a simple follow-up process for overdue work, including scheduled reminders and a quick way to check who still owes money.
Handle UK trade tax fields
For UK businesses that need invoice fields for VAT, reverse-charge VAT, and CIS deductions without building the invoice manually each time.
Replace spreadsheets for basic invoicing
For sole traders and small limited companies that want a lightweight invoicing flow without spreadsheets or a full accounting package.
Pros and Cons
Pros
- Creates invoice drafts directly from a WhatsApp message.
- Emails a PDF invoice to the customer after user approval.
- Includes payment reminders on a 7, 14, and 28 day schedule.
- Supports VAT, construction reverse charge VAT, and CIS deductions.
- Offers a free tier with 3 invoices per month.
Cons
- Custom sending domains are not available yet.
- WOPA is not currently HMRC-recognised or MTD-compatible software.
FAQ
Do I need to download an app?
No. WOPA lives in WhatsApp, where you send the job details and approve the draft before anything is emailed out.
Can I edit before sending?
Yes. WOPA shows a draft invoice and asks for confirmation before sending the PDF or a follow-up message.
Can I turn reminders off?
Yes. You can pause or stop reminders for a specific invoice, and marking an invoice as paid also stops future reminders.
Do customers need WhatsApp?
No. Customers receive the invoice by email as a PDF attachment; WhatsApp is the control surface for the sender.
Does WOPA support VAT?
Yes. WOPA supports standard VAT, reverse-charge VAT for construction, and CIS deductions for subcontractors.
Quick Facts
- Category
- WhatsApp invoicing
- Primary users
- UK tradespeople, sole traders, and small limited companies
- Platform
- WhatsApp chat workflow with email delivery
- Pricing
- Free for 3 invoices per month; founder pricing is £9.99/month for early beta customers
- Source domain
- mywopa.com
- Status
- Live beta
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