How to Read Your Electricity Bill: Every Line Item Explained

Electricity bills are designed to be factual and compared against a benchmark, not necessarily to be easy to read. Here's what every section actually means, so you can tell at a glance whether you're getting a fair deal.

The basics at the top

• NMI (National Metering Identifier) — a unique number for your specific connection point. It's not your account number, it's tied to the property and therefore your meter.

• Billing period — the exact dates this bill covers. Worth checking, since periods could be monthly or quarterly which can make comparisons difficult or misleading.

• Total amount due and due date — self-explanatory, but check it against the estimated annual cost figure further down (more on that below!).

Daily supply charge

A fixed fee, charged per day just for the pleasure of being connected to the grid — you pay it whether you use 1 kWh or 100 kWh that day. This part of your bill has nothing to do with how much power you used, which is exactly why it's been a hot topic lately: regulators recently introduced separate price caps on supply charges (previously only the total bill was capped), and that's driven noticeable increases in this line item for many households, often offset by lower usage rates elsewhere on the bill.

Usage charges

This is where it gets more complex, depending on your tariff type:

• Flat rate (single rate) — one rate per kWh no matter when you use it. It’s simple to understand but doesn't reward shifting your usage to cheaper times.

• Time-of-use (ToU) — different rates depending on the time of day:

  • Peak — typically late afternoon/evening, the most expensive.

  • Shoulder — the middle ground, between peak and off-peak.

  • Off-peak — usually overnight, the cheapest.

  • Solar soak (a newer category on some plans) — a low-cost window in the middle of the day when solar generation is highest.

• Controlled load — a separate usually cheaper rate for things wired on their own circuit. Most commonly electric hot water systems, that are charged overnight.

If your retailer offers a Solar Sharer-style plan, you may also see a free usage window (usually three hours around midday) — anything used outside that window reverts to standard rates.

Solar feed-in (export) credit

If you have solar panels this is a credit — the rate you're paid for electricity you export back to the grid. It's worth checking this figure on its own, separately from your usage rate because feed-in tariffs have been trending downward across the market for some time. A retailer can offer a competitive usage rate while quietly paying a below-average feed-in rate, so the two need to be compared independently.

GST

Added at 10% on top of the total. Something, something, death and taxes.

Concessions and rebates

If you're eligible for a government energy concession or rebate, it'll usually show as a separate line item or credit, distinct from anything your retailer offers. Worth checking this is actually being applied — concessions sometimes need to be set up directly with your retailer rather than applying automatically.

The box that actually matters: estimated annual cost / comparison rate

Most Australian bills are required to include an estimated annual cost based on your usage pattern, plus a reference to the regulator's comparison rate (the DMO or VDO, depending on your state). This is the single most useful number on the page for working out whether your plan is actually competitive — far more useful than comparing individual line items, since a plan can look cheap on the usage rate and expensive overall once the supply charge and any fees are added back in.

Reading it all together

Let’s be honest, we take a glance at how much it’s costing us this month and either throw it away or shove it in a file - never to see the light of day again.

Individually, none of these line items tell you much. A low usage rate can be cancelled out by a high supply charge; a generous feed-in tariff can mask a mediocre usage rate; a "discount" can be calculated off an inflated base rate. The only number that actually matters is the bottom-line annual cost for your usage pattern, compared against what else is available.

That's the exact comparison SwitchBuddy runs for you. Upload your bill and we'll read every line item — supply charge, usage rates, feed-in credit, fees, the lot — and tell you plainly whether you're on a good deal or paying more than you need to.