Petroleum Resource Rent Tax (Interest on Underpayments) Act 1987

This is a very short law that does one simple thing: it officially creates an interest charge for people or companies who underpay their Petroleum Resource Rent Tax (PRRT).

What it does:

• Imposes interest on unpaid or underpaid PRRT amounts
• The actual rules about how much interest and when it applies are in a different law — the Petroleum Resource Rent Tax Assessment Act 1987 (specifically section 65)
• This Act just makes that interest legally valid and enforceable

Who it affects:

• Oil and gas companies operating in Australian offshore areas who owe PRRT
• Any taxpayer who underpays their PRRT liability

Why it matters: Without this Act, the interest charges described in the Assessment Act might not be legally enforceable. This Act is the "imposition" mechanism — it gives the government the constitutional power to collect that interest. It's a technical but necessary piece of the tax collection machinery.