Back to Invoices

TAX INVOICE

Outstanding

Invoice Number

#BB-2026-0197

Client

Ravensworth Civil Pty Ltd

[email protected]

Invoice Date

26 Mar 2026

Due Date

09 Apr 2026

5 line items, 4 of them billable Done

Date	Item	Description	Rate	Qty	GST	Line Total
02 Mar 2026	Site survey and scope Hourly	Fixed price. Two visits to the Marlow Street depot, scoping the ledger cutover.	–	–	10%	$1,850.00
06 Mar 2026	Ledger integration build Hourly	Billed at the agreed rate against the attached timesheet.	$165.00	24	10%	$3,960.00
17 Mar 2026	Reconciliation review Hourly	Matching recorded payments against issued invoices for the quarter.	$165.00	9	10%	$1,485.00
20 Mar 2026	Statement template revision Hourly	Fixed price. Second revision, agreed in writing before the work started.	–	–	10%	$1,005.00
06 Mar 2026	Travel to depot, return Hourly Unbillable	On the timesheet for the record. Carried at zero so it never reaches the total.	$0.00	3	10%	$0.00

Add Line Item

Payment Details

ABN:54 118 402 663

Bank:Harbourline Studio

BSB:062 918

Account:4471 0263

No ChargeShows work done, nothing owed

Discount 0 %

Subtotal$8,300.00

Total GST (10%)~~Summed from the rate on each line, rounded once~~ $830.00

AMOUNT DUE$9,130.00 AUD

BALANCE DUE$9,130.00

+ Add Payment

Save as Draft Mark Paid Delete

Why the billing mode has to be sent, not just stored

This invoice is built from its lines. Saving it sums every line total, sums the per-line GST at each line's own rate, and rounds both once. The unbillable travel line sits at 0.00, which is how it stays on the timesheet without reaching the money.

An invoice can instead be billed as a single hourly engagement, where the amount is hourly_rate × hourly_quantity. Over the API that mode is not read from the stored record. The recalculation is guarded on is_hourly arriving in the request body, so a PATCH sending a new hourly_quantity on its own leaves amount, GST and total exactly where they were. The caller has to name the billing mode before anything moves the money.

This screen reconciles

1,850.00 + 3,960.00 (24 × 165.00) + 1,485.00 (9 × 165.00) + 1,005.00 + 0.00 (unbillable) = 8,300.00 subtotal

GST = 185.00 + 396.00 + 148.50 + 100.50 + 0.00 = 830.00, exactly 10% of 8,300.00 because every line here is taxable at 10%

Total = 8,300.00 + 830.00 = 9,130.00, nothing paid against it yet, so BALANCE DUE is the same 9,130.00

Brontiq Books is a real, shipped product. This screen is drawn from it, and every client, contact, email, ABN, bank detail, invoice number, date and figure on it is invented. Invoice BB-2026-0197 carries this same $9,130.00 on the ledger and statement screens.