WHMCS Tax Setup: UK and EU VAT, Australian GST and US Sales Tax

Which WHMCS tax setup do you need for your region?

Start from where your business is registered. If it is not registered, leave Tax Support off: GOV.UK's Charging VAT page says you must register for VAT to start charging it.

1. Not registered anywhere: leave Tax Support off for now.
2. UK or EU business: VAT Mode with VAT number checks.
3. Australian business: one 10% GST rule, usually with GST-inclusive prices.
4. Collecting US sales tax: one rule per state where you collect.
5. Anywhere else: get your accountant's rules first.

How does tax work in WHMCS 9.1?

Tax appears only when Tax Support is on, a rule matches the client's country and state, the item is taxable, and the client is not tax exempt.

Taxed Items covers domains, billable items, late fees, custom invoices, credit notes and debit notes. Products are untaxed by default: per Enable Taxes for a Product, edit each one at Configuration > System Settings > Products/Services and check Apply Tax. Product addons are not in the Taxed Items list, so I confirm on a test order that addon lines carry tax.

Compound Tax "calculates compound tax after and in addition to a primary tax", adding a Level 2 rule on top of Level 1. Leave it off unless your accountant says otherwise.

Should you use inclusive or exclusive tax in WHMCS?

Use Exclusive when you quote prices before tax, and Inclusive when the price you advertise already contains tax. The docs give both formulas:

• Exclusive: Tax Amount = Item Price x (Tax Rate / 100). A £10 plan at 20% becomes £12.
• Inclusive: Tax Amount = (Item Price / (100 + Tax Rate)) x Tax Rate. An A$11 plan at 10% contains A$1 of GST.

Deduct Tax Amount, with Inclusive tax, removes tax from orders that match no rule, using your default country's rate, so a client outside every rule does not pay the tax portion. Calculation Mode either rounds tax per line item to two decimals or calculates it on the sum; the docs' example of 11 items at $2.21 with 20% tax gives $4.84 one way and $4.86 the other. Pick one before the first invoice and keep it.

How do you set up UK VAT in WHMCS?

Follow Configure VAT for the UK:

1. At Configuration > System Settings > Tax Configuration, set Tax Support to ON.
2. Enter Your Tax ID/VAT Number so it prints on invoices.
3. Set Customer Tax IDs/VAT Numbers to ON and save.
4. On the VAT Settings tab, set VAT Mode to ON and enter a VAT label name.
5. Choose a VAT Number Validation method, then a UK VAT Validation Mode.
6. Click Create Rules, then choose taxed items and products.

The docs' UK example is United Kingdom, Apply Rule to All States, 20.0, which matches GOV.UK's VAT rates page: "The standard VAT rate is 20%". Add that rule on the Tax Rules tab if Create Rules did not.

GOV.UK's When to register for VAT page requires registration once taxable turnover for the last 12 months goes over £90,000, or will within 30 days. After that, the Charging VAT page says "invoices must include your VAT number and display the VAT separately".

Set Your Home Country to United Kingdom and tick Home Country Exclusion, which always charges VAT on UK billing addresses, so UK business clients pay VAT even with a valid number.

For EU consumers, GOV.UK's digital services guidance lists "website supply or web hosting services" as electronically supplied and says such supplies to consumers outside the UK "may be liable to VAT in the country where the consumer is based". The EU One Stop Shop offers non-EU businesses a Non-Union scheme: one registration, one return, one payment.

How do you set up EU VAT in WHMCS?

The steps in Configure VAT for Europe match the UK list without the UK validation mode. Create Rules sets up the VAT rules; Auto Configure VAT Tax Rules rebuilds them "using the appropriate VAT rate for each EU country", and Automatically Update VAT Rules repeats that check in the daily cron, so my WHMCS cron jobs guide matters here.

Your Europe's VAT rules and rates table lists each country's standard rate (Germany 19, Ireland 23, Finland 25.5) and says reduced rates do not apply "in most cases" to electronically supplied services. Its cross-border VAT page says services to a business in another EU country usually carry no VAT; the customer pays "using the reverse charge procedure". Electronic services to consumers are taxed in the customer's country, with a EUR 10,000 threshold below which they may be taxed where you are established.

With Your Home Country set to Germany, Home Country Exclusion, full validation and Auto Tax Exempt on, a German host gets:

The 9.1 pages I read do not describe a reverse charge note on invoices. Get the wording from your accountant and add it in the invoice template or a hook; my invoice template guide shows where.

Charging the right VAT is a separate job from sending the invoice as structured data, which my WHMCS e-invoicing guide covers country by country.

Two add-ons I sell help once VAT is set up: TaxPilot shows the tax you collected split by B2B and B2C clients, and the DATEV Export posts reverse charge and OSS invoices to their own revenue accounts for a German tax advisor.

How does WHMCS VAT number validation work?

VAT Number Validation offers Do Not Validate, Validate Format During Checkout, Validate with Relevant Authority, or Validate at Checkout and with Relevant Authority. The format check covers the 27 EU countries, Northern Ireland and the United Kingdom.

• Auto Tax Exempt marks a client tax exempt when their number validates.
• Revalidation: saving a client's profile rechecks the number with VIES for EU numbers and HMRC for UK numbers; an invalid number removes the exemption for new invoices.
• UK VAT Validation Mode: WHMCS strongly recommends Remote Verification and warns other modes "may result in additional VAT liability".
• Custom Field Migration moves VAT numbers from the old EU VAT Addon's custom field into the client record.

How do you set up Australian GST in WHMCS?

Add one rule: GST, Australia, Apply Rule to All States, 10. The ATO's How GST works page calls GST "a broad-based tax of 10%" and says registered businesses "include GST in the price they charge", so Inclusive tax fits. No VAT Mode is needed.

Per Registering for GST, you must register at GST turnover of $75,000 or more ($150,000 for non-profits), within 21 days, and you need an ABN first. Enter that ABN as Your Tax ID/VAT Number so it prints on every invoice.

The ATO's Tax invoices page drives the template work:

• Provide a tax invoice within 28 days when asked, unless the sale is $82.50 including GST or less.
• Under $1,000, show that it is a tax invoice, your identity and ABN, the date, items with price, the GST amount and how much is taxable.
• When GST is exactly one-eleventh of the total, "Total price includes GST" can replace a separate figure; from $1,000, add the buyer's identity or ABN.
• Emailed PDF invoices are fine if they hold every required detail.

Make your template call the document a tax invoice, and ask your accountant which Calculation Mode matches the ATO rounding rule you use.

How do you set up US sales tax in WHMCS?

There is no single US entry in WHMCS: you add a rule for each state where you collect. Take Texas. The Comptroller's Sales and Use Tax page says Texas imposes "a 6.25 percent state sales and use tax" on most goods and taxable services, and local jurisdictions "can also impose up to 2 percent" for a combined maximum of 8.25 percent.

In WHMCS that is United States, Texas, 6.25, with Exclusive tax. The rule form stops at state level, with no city or ZIP field, so it cannot charge one Texas address 6.25% and another 8.25%. Whether hosting counts as a taxable service in Texas is for the Comptroller's guidance or your accountant. Tax follows the client's address, not their currency, as my WHMCS multi currency setup guide explains.

How does WHMCS number paid invoices for VAT?

Turn on Proforma Invoicing/Sequential Paid Invoice Numbering on the VAT Settings tab. Enable Proforma Invoicing says "Some accounting practices, particularly for EU-based companies, require you to use sequential invoice numbers for paid invoices", usually with proforma invoicing as well.

• Sequential Invoice Number Format applies when an invoice becomes Paid, for example WHMCS2007-{NUMBER}.
• Next Paid Invoice Number rises by 1 with each payment; Auto Reset Numbering can be Never, Monthly or Annually.
• Set Invoice Date on Payment moves the invoice date to the payment date.
• Enable Proforma Invoicing sits on the Invoices tab at Configuration > System Settings > General Settings.

Per Configure Invoice Immutability, 9.1 locks non-Draft invoices by default, records adjustments as credit and debit notes, and tells you to "Reissue invoices to correct details like the invoice date or tax rate".

How do you change a tax rate in WHMCS?

Delete the old rule and create one with exactly the same name, country and state. Update Tax Rates says to do it at midnight, or as late as possible before the cron runs; for a rate effective 4 January, its example changes it on 3 January. New invoices get the new rate; existing ones keep the old. That example, 17.5% to 20%, mirrors the UK change GOV.UK dates to 4 January 2011.

Under Exclusive tax or Deduct Tax Amount, fixed-amount subscriptions at gateways such as PayPal may no longer match the new invoice total, so cancel them and start new ones from the next invoice, the kind of work I cover under WHMCS payment gateway integration. The tutorial also offers SQL to rewrite unpaid invoices on self-hosted installs; on 9.1, with invoices locked, I reissue instead.