How to read a laundromat gas bill

The short version

A commercial gas bill is built from four things: how much gas you used, the rate you pay for it, a fixed daily charge just for being connected, and everything else (fees, adjustments, GST). If you can follow those four, you can check any bill from any retailer.

1. Usage, measured in megajoules (MJ)

Gas is billed in megajoules. Your meter may count cubic metres, and the retailer converts that to MJ using two numbers printed on the bill: a heating value (how much energy is in each cubic metre) and a pressure correction factor. Both can change a little between bills, so it is worth glancing at them. A big jump in either, with no change in how many dryer cycles you ran, is a question for your retailer.

2. The usage rate, often in tiers

Many business plans charge a higher rate for the first block of gas and a lower rate for the next block, so a single bill can show two or three usage lines. Check that the MJ in each block adds up to your total usage, and that each block multiplied by its rate matches the amount printed. If the rates changed part-way through the period, the bill should show a separate line for each part.

3. The daily supply charge

This is a fixed amount for every day in the billing period, whether you use gas or not. The check is simple: days in the period × daily rate. If the number of days looks wrong (for example, 95 days on what should be a quarterly bill), or the daily rate is higher than on your last bill, ask why. A supply charge that quietly doubles is easy to miss when you only look at the total.

4. Meter reads: actual or estimated

The bill says whether the reads were actual or estimated. Estimates are not wrong by definition, but they are guesses. If the estimate is too low you can face a catch-up bill later. Our guide to estimated reads and catch-up bills explains what to do. Also check that this bill's start read matches the previous bill's end read. A gap between the two means some gas has not been billed yet.

5. Fees, credits and adjustments

Look for late payment fees, service fees, reconnection fees and credits. Two patterns come up often: a late fee on a bill that was already paid, and fees added to a corrected or reissued bill. Both are worth questioning in writing. More in bill errors to look for.

6. GST

GST is 10 percent. Business bills often show amounts excluding GST in the line items and add GST at the end, while some retailers show GST-inclusive rates. Read the small print on your bill so you do not compare ex-GST rates against inc-GST rates.

A quick checklist for every gas bill

• Days in the period are right and match the previous bill's end date.
• Start read equals the last bill's end read.
• Each usage block × its rate equals the printed amount.
• Daily supply rate × days equals the supply charge.
• No fees for something you have already paid or fixed.
• The total, GST and amount due add up.

Doing this every quarter, for every shop

None of this is hard. The difficulty is volume: several shops, gas and electricity, bills that arrive in different formats and get reissued. LaundroMetrics reads each bill, recalculates every line and lists what to question before you pay. See the gas bill checker.