What goes on an estimate

The parts an estimate needs

Most of it looks like an invoice, because it is the same shape of document pointed the other way — invoice vs estimate covers what changes between the two. Four fields do the work that an invoice never has to do.

• Who and where. Your details, the customer’s, and the address the work happens at when it is not theirs. On quoted work the job address is often the only thing distinguishing two estimates for the same person.
• Its own number. An estimate sequence separate from your invoices — EST-0044 — so the quotes that go nowhere leave no holes in your invoice numbering.
• A date and an expiry. When you wrote it, and how long the price holds.
• The scope, priced. Lines describing what you will do, with quantities where quantities exist.
• What you have assumed and what you have left out. The section that decides whether this document protects you.
• What happens next. The deposit, if there is one, and how the customer says yes.

Write the scope in the units of the job

An estimate is read by someone deciding, so it should be legible to a person who does not do your trade. That means describing the work in the units they can picture — rooms, metres, fittings, visits — rather than in your internal shorthand.

Where a quantity exists, state it: 22 m² of decking, 9 linear metres of handrail, six radiators, four zones. Quantities do two things at once. They let the customer sanity-check the price against anything else they have been quoted, and they give both of you a shared basis when the job turns out to be bigger than the plan.

Break the scope into lines that could each be dropped. A single-line estimate for $6,200 offers a yes or a no. The same work in four lines lets a customer with $5,000 ask which part can wait, which is a conversation that ends in a job.

Assumptions and exclusions

This is the part of an estimate that has no equivalent on an invoice, and it is the reason experienced trades write quotes at all.

Assumptions are the conditions your price depends on. “Assumes the existing sub-frame is sound.” “Assumes access through the side gate for a barrow.” “Assumes the boiler is accessible without removing the units.” If one turns out to be false, the price changes and the document already said why.

Exclusions are the things a reasonable customer might assume are included and are not: making good, painting, disposal, scaffolding, permits, moving furniture. Every trade has three or four that come up constantly. Write your own list once and reuse it.

Where you know work might be needed but cannot see it yet, a provisional sum is more useful than either. It is a stated allowance for a specific possibility — replacing up to four rotten posts, say — charged only if it happens, and adjustable once you can see. It keeps the total honest and stops the customer discovering an extra on the final bill.

How long the price holds

Materials move and your calendar fills, so an estimate should say when it stops applying. Two weeks to a month is the usual window in the trades, and the sentence is simply “this price is held until 24 October”.

It is not a formality. Without it you are exposed to someone accepting a nine-month-old price after your costs have moved, and the conversation where you explain that is much worse than the one where you re-quote a lapsed estimate. Whether a given price binds you at all depends on your agreement with the customer and on the rules where you trade, so say plainly on the document whether the figure is fixed or indicative.

Deposits, and saying yes

If you take money up front, the estimate is where that is introduced: how much, when it is due, and what it secures — a date in the calendar, materials ordered, or both. A deposit mentioned for the first time after acceptance reads as a change of terms.

Say how to accept, too. For most small jobs a reply is enough, and asking for one gives you something in writing. For anything with a deposit, the deposit is the acceptance.

Where estimates go wrong

• One line, one number. Nothing to check, nothing to negotiate except the total.
• No expiry. The price is now open-ended.
• Nothing excluded. Every assumption the customer made is now yours.
• An unpriced unknown described in conversation. Put an allowance on the document or say plainly that it will be quoted separately.
• Estimate numbers taken from the invoice sequence. Quotes that go nowhere leave gaps you will be asked about.
• An invoice that does not resemble the estimate. Keep the line order and wording; add changes as their own lines.

Making the document

Invoice Tiger does estimates on the same workflow as invoices: the same editor, an expiry date instead of a due date, and a separate EST- number sequence so a quote that never becomes work leaves your invoice numbering intact. When the job is done you build the invoice from the same saved customer and the same saved line items, which is what keeps the two documents looking like each other.

One thing worth being straight about: the free web generator on this site makes invoices. There is no estimate mode in it, and a document it produces says INVOICE at the top — so it is the right tool for billing the job once the quote is accepted, and the wrong one for the quote itself.

If you would rather work on the estimating than the paperwork, how to write an estimate covers the part before the document: what to record on site, how to price something you cannot see yet, and which jobs are worth quoting at all. And for the trades where quoting is most of the job, the contractor, painting and plumbing pages each cover how a quote turns into a bill in that trade.