The short version
- An estimate is your best guess at the price before the work. It can change, and the client should know by how much.
- A quote is a fixed price for a clearly defined job, usually valid until a date.
- An invoice asks for payment for work done, with a due date.
- In Ontario, a consumer generally cannot be charged more than 10% over an estimate without agreeing in writing.
The difference at a glance
| Estimate | Quote | Invoice | |
|---|---|---|---|
| What it says | "It should cost about this." | "It will cost exactly this." | "You owe this. Please pay by this date." |
| When | Before the work, when the scope is not fully known. | Before the work, when the scope is clear. | After the work, or at agreed stages. |
| Can the price change? | Yes, within limits you state (and the law allows). | Not for the work described. | No. Fix mistakes with a new invoice. |
| Key date | Expires on | Valid until | Due on |
People often use "estimate" and "quote" for the same thing, and many apps, Sumocat included, use one document type for both. What matters is what the document says: whether the price is a guess or a promise, and until when it stands.
When to send an estimate
Send an estimate when you cannot know the full price until you start. A plumber chasing a leak inside a wall, a mechanic who has not opened the engine, a renovation where the subfloor might be rotten: each can give a careful best guess, but not a promise.
Make the uncertainty explicit. Say what the estimate covers, what it does not, and what would change it ("if the subfloor needs replacing, that is $9 per square foot extra"). Clients accept a range they were told about; they argue about a surprise.
Ontario’s 10% rule
Under Ontario’s consumer protection law, a business that gives a consumer an estimate cannot charge more than 10% above it, unless the consumer agrees to the extra charges in writing. If you go over without that agreement, the consumer can ask for the work at the estimated price. Other provinces and states have their own rules for consumer estimates, so check yours.
Worked example
An Ontario estimate of $4,000 before tax
- Estimate
- $4,000.00
- 10% above the estimate
- $400.00
- Most you can charge without written agreement
- $4,400.00
If the job is going to cost more, stop and get the client’s written agreement to a revised price before you do the extra work.
When to send a quote
Send a quote when you can see the whole job: a painter who has measured every room, a photographer pricing a two hour shoot, a cleaner who has walked the house. A fixed price is easier for the client to say yes to, and you carry the risk of going over, so price it with care. How to price a job covers hourly, flat rate and markup.
Give every quote a "valid until" date, usually 14 to 30 days out. Material prices and your schedule change, and an open ended quote can come back to bite you months later.
| Item | Qty | Rate | Amount |
|---|---|---|---|
| Walls and ceilings, 3 rooms1150 sq ft × CA$2.40 | 1150 sq ft | CA$2.40 | CA$2,760.00 |
| Trim and doors1 job × CA$640.00 | 1 job | CA$640.00 | CA$640.00 |
| Paint and supplies1 job × CA$480.00 | 1 job | CA$480.00 | CA$480.00 |
Fixed price for the work listed. Valid until Dec 17, 2026. 25% deposit to book the dates, balance on completion.
When to send an invoice
Send an invoice when payment is due: when the work is done, or at a stage you agreed, like a deposit or a milestone. It should match what the client accepted. If the job changed, the invoice shows the change as its own line, so the client can trace every dollar back to the estimate or quote.
An invoice carries what the others do not: an invoice number, a due date, and how to pay you. How to write an invoice that gets paid on time goes through every part.
From estimate to invoice in Sumocat
In Sumocat an estimate carries an expiration date, and you can add a deposit and milestones that always add up to the total. When the client says yes, turn it into an invoice with the same client, lines and taxes. All of that is free.
With Sumocat Pro PRO your client can accept the estimate on its web page. Sumocat records the date and time and creates the first invoice for you. An expired estimate can no longer be accepted, which keeps old prices from coming back. If the job needs more than a price, Pro PRO also lets you send a contract for your client to sign online.
Write the estimate first
Lines, taxes and an expiry date, then a clean PDF. Free in your browser, no sign up.
Prefer the word quote? The quote generator is the same tool, worded as a quote. There are filled in estimate templates for every trade too, like painting and contractors.
Questions
Is a quote legally binding?
Once a client accepts a quote, it can become part of your agreement, and you may be held to the price for the work it describes. Put the scope, the price and the valid until date in writing. For anything large, a written contract is safer, and a lawyer can tell you how the rules apply where you work.
Can I charge more than my estimate?
Sometimes, within limits. In Ontario, a consumer generally cannot be charged more than 10% above an estimate unless they agree to the extra in writing. Wherever you are, tell the client as soon as you know the price is rising and get their agreement before doing the extra work.
Should an estimate include tax?
Yes. Show each tax as its own line and the total with tax, so the client is not surprised by the invoice. Our sales tax calculator works out GST, HST, PST, QST and US sales tax.
Do I need an estimate for every job?
No. Small, quick jobs at a known price can go straight to an invoice. An estimate pays off when the job is larger, the client is new, or the price could change.
Sources
The official pages this guide relies on, with the date we last checked each one. Rules and rates change, so check the page itself before you rely on it.
- Government of Ontario, Business guide to consumer protection: key consumer protection concepts. www.ontario.ca/document/business-guide-consumer-protection/key-consumer-protection-concepts Checked .