Lexware Office Sync for WHMCS
Send WHMCS clients, invoices and credit notes to Lexware Office (formerly lexoffice) and bring payments back, with VAT cases mapped for you.
What will the Lexware Office sync do?
It keeps your bookkeeping in Lexware Office (formerly lexoffice) in step with WHMCS without copying invoices by hand. A new WHMCS client becomes a Lexware contact. Each finalized invoice and each WHMCS 9 credit note goes to Lexware with its lines, tax rate and tax type: domestic, reverse charge, EU one-stop shop (OSS) or outside the EU. When a payment is recorded in Lexware, the matching WHMCS invoice is marked paid.
This product is built to order: you get the license key at purchase and the download within 15 business days.
What does WHMCS already do, and what does this add?
WHMCS keeps its own invoices and has no connection to Lexware Office. Without one, every invoice is typed or imported into Lexware by hand. The addon adds the contact and invoice sync, the tax mapping, payment status in both directions and a log of every request.
What is included?
| Part | What you get |
|---|---|
| Contacts | WHMCS clients created and updated as Lexware contacts, including a Leitweg-ID for public-sector buyers |
| Invoices and credit notes | Finalized WHMCS invoices and WHMCS 9 credit notes sent to Lexware |
| Tax mapping | Domestic, reverse charge, EU OSS and non-EU cases set per client |
| Payments | Payments recorded in Lexware mark the WHMCS invoice paid |
| Optionally, the Lexware PDF attached to the WHMCS invoice email | |
| Queue and log | Requests sent within the Lexware API rate limit, with a log and retry for failures |
Who is it for?
Hosting companies, agencies and software sellers in Germany that bill in WHMCS and keep their books in Lexware Office, or whose tax advisor works from it. Lexware can also issue e-invoices, so this is a second route to German e-invoicing besides my XRechnung and ZUGFeRD addon.
What do you need, and what are the limits?
Requirements: WHMCS 8.13 or 9.x (I confirm your exact version at purchase), PHP 8.1 or newer, the WHMCS cron running, and a Lexware Office account with an API key.
Limits: decide before you start whether WHMCS or Lexware is the invoice of record, because both number invoices; I set this up with you. The addon syncs invoices, credit notes, contacts and payments, not expenses or bank accounts. It is not tax advice.
It costs $149 once for a lifetime license with twelve months of updates and support, the license key at purchase and the download within 15 business days, and a seven-day refund window.
Key features
- WHMCS clients synced as Lexware Office contacts
- Finalized invoices sent to Lexware with lines and tax
- WHMCS 9 credit notes sent as Lexware credit notes
- Tax types mapped: domestic, reverse charge, EU OSS, non-EU
- Leitweg-ID on contacts for public-sector buyers
- Payments in Lexware mark the WHMCS invoice paid
- Optional Lexware PDF in the WHMCS invoice email
- Request queue within the API rate limit
- Log of every request with retry for failures
Why customers buy this module
- →No more typing WHMCS invoices into Lexware Office
- →Your tax advisor sees the same numbers you do
- →Payment status stays the same in both systems
- →A second route to German e-invoices through Lexware
Frequently asked questions
Does it work with lexoffice?
Yes. lexoffice is now called Lexware Office, and the addon uses its public API. Your existing account and API key work as they are.
Which system numbers the invoices?
You choose. Either WHMCS keeps numbering and Lexware stores the invoice as a voucher, or Lexware creates the invoice and its number is written back to WHMCS. I set this up with you before the first sync, because changing it later leaves gaps.
When will I get it, and what if you can't deliver?
You get the license key at purchase and the download within 15 business days of purchase. If I do not deliver it in that time, you get a full refund. Otherwise the store's seven-day refund window applies.
Technical specifications
- WHMCS
- 8.13 and 9.x (confirmed at purchase)
- PHP
- 8.1+
- Accounting
- Lexware Office (formerly lexoffice) public API
- Availability
- Built to order, delivered in 15 business days
- License
- Lifetime, 1 year of updates and support included
- Delivery
- Instant download and license key
- Refund window
- 7 days
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