Tradify ↔ Xero (UK): how to stop duplicate invoices and contacts before they snowball

UK trades teams often find a surprise pile-up of duplicates after connecting Tradify to Xero—double invoices, doubled payments, and cloned contacts. This guide gives you a clean, UK-ready setup and a rapid clean‑up workflow, so you can keep job admin in Tradify and have tidy books in Xero.

Who this is for

• UK electrical, plumbing, HVAC, and building firms using Tradify + Xero
• Owners, office admins, and bookkeepers who want one source of truth and clean reconciliations

The 3 rules that prevent 95% of duplicates

1. One source of truth for invoices

• Choose where invoices are created and approved. Best practice: create/approve in Tradify and send to Xero as Draft/Approved (not both).
• Decide numbering: either let Xero assign numbers (send as Draft) or keep Tradify numbers with a unique prefix (e.g., TD‑000123).

2. One source of truth for payments

• Record a customer payment once (either in Tradify or in Xero bank rec), not both. Duplicate payments double your revenue and make bank rec messy.

3. One source of truth for contacts

• Create/edit contacts in one place. Avoid manually re‑creating the same customer in Xero after it already exists from Tradify.

Recommended UK setup (10‑minute checklist)

• Tradify > Settings > Integrations > Xero:
  • Turn on “Use Xero invoice numbering sequence” OR set a Tradify invoice prefix (e.g., TD‑) and Next Invoice Number that won’t clash with Xero.
  • Choose to send invoices as Draft to Xero if you want Xero to allocate numbers and allow last checks.
  • Confirm payment sync behaviour (if enabled, don’t also add the payment in Xero).
• Contacts: import once (Xero → Tradify) if you’re migrating, then stop dual entry. New customers are created in Tradify only going forward.
• VAT/CIS: ensure your Xero VAT codes (including Domestic Reverse Charge and CIS settings) are correct; Tradify won’t fix VAT boxes if the Xero codes are wrong.

Clean‑up playbook (if duplicates already exist)

1) Stop the bleeding

• Pause sending invoices from Tradify until clean‑up is finished.
• Pick a numbering strategy (Xero‑assigned or TD‑prefix in Tradify). Note it on your team SOP.

2) Find and remove duplicate invoices in Xero

• In Xero: Business → Invoices → All. Search by Number/Reference/Amount. Export to CSV and sort by number/amount to spot twins.
• Delete or void based on status:
  • Draft/Awaiting Approval → Delete.
  • Awaiting Payment → Void (then re‑reconcile the bank line to the surviving invoice).
  • Paid → Remove & Redo the payment, then Void the duplicate. Re‑reconcile to the correct invoice.

3) Fix duplicate payments

• In Xero, use Remove & Redo on the wrongly matched payment, then match the bank line to the correct invoice only.
• If Tradify pushed a payment and you also receipted it in Xero, remove one.

4) Merge duplicate contacts in Xero

• Keep the contact record created/linked by Tradify if possible. From the duplicate contact: Options → Merge → choose the one to keep.
• After merging, run one test sync from Tradify so future invoices link to the surviving contact.

Golden settings and habits

• Prefix prevention: If you keep Tradify numbering, use a prefix (TD‑) so no clash with historic Xero invoices (e.g., INV‑000123).
• Draft first: Sending as Draft to Xero lets you fix VAT codes, references, and tracking before approval.
• Don’t edit in two places: If you need to change an invoice after sending, reset it to Draft in Tradify, edit, and resend. Don’t also tweak the copy in Xero.
• Contact uniqueness: If two clients share a name, append a differentiator (site or ID) in the contact name in Tradify before sending to Xero.

Troubleshooting quick wins

• “Invoice number is not unique” on sync: renumber in Tradify (copy to a new number) or switch to Xero numbering and resend.
• Payments showing twice in Xero: remove the duplicate payment (Remove & Redo), then re‑match the bank line.
• Can’t edit an invoice because it’s already in Xero: reset the Tradify invoice to Draft, delete/void the Xero copy, then resend from Tradify.

Example SOP (copy/paste for your team)

Invoice creation: Tradify only → Send to Xero as Draft
Numbering: Xero allocates numbers (or TD‑ prefix in Tradify)
Payments: Record in bank rec (Xero) only; do not add payment in Tradify
Contacts: Create in Tradify only; never create the same contact in Xero
End‑of‑day check: Xero Drafts reviewed/approved by 4pm

FAQs

• Can I approve some invoices in Xero and some in Tradify? You can, but don’t approve the same invoice in both. Keep one path per document.
• Will Xero allow two invoices with the same number? On approval/sync, Xero enforces uniqueness—duplicates cause errors or get blocked.
• Should I sync credit notes? Yes, but follow the same rules: create in one system and let the sync post to the other.