Two settings that are much easier to configure correctly before you issue your first invoice than to correct afterwards.

Tax

1. Go to Settings → Invoice Settings.
2. Enter your tax rate and the label your customers should see, such as VAT or GST.
3. Add your tax registration number so it appears on invoices, if you are required to show it.
4. Save, then generate a test invoice and confirm the figures are exactly what you expect.

The configured rate applies to invoices generated after you save it. Existing invoices are not retrospectively recalculated, which is normally what you want — an issued invoice should not change after the fact. Get the rate right before going live.

Promo codes

1. Go to Promo Codes → Add.
2. Set the code itself — short and easy to type.
3. Choose a percentage or fixed-amount discount.
4. Set an expiry date and a maximum number of uses.
5. Restrict it to particular packages if the offer is not meant to apply to everything.

Points worth watching

• Always set an expiry and a usage cap. An open-ended code will circulate on coupon sites indefinitely.
• Decide whether the discount applies to renewals or only to the first term. A percentage discount that silently recurs forever is an expensive mistake.
• Check the interaction with tax on a test invoice — confirm the discount is applied before tax is calculated, as you intend.
• Test every code by placing a real order before you publish it.