Quotation vs Estimate vs Proposal: What's the Difference?

The Confusion Is Understandable

Estimate, quotation, and proposal are all pre-sale documents. All three involve you putting a price or description of work on paper before you've been paid. But they commit you to very different things — and using the wrong word can cost you money or lose you the job.

What Is an Estimate?

An estimate is an informed approximation of what the work will cost. It is not binding. If the actual cost turns out higher, you can (within reason) charge more — though significant overruns require communication.

Estimates are used when:

The full scope isn't yet clear

The job involves unknowns (e.g. what's behind a wall in a renovation)

You want to give a client a ballpark before committing to a fixed price

Language to use: "approximately," "estimated cost," "subject to change based on actual scope."

A client who receives an estimate understands they may pay more or less than stated. If you give an estimate of $800 and bill $1,200, expect a conversation — but it's not necessarily a breach of agreement.

What Is a Quotation?

A quotation (or quote) is a fixed price offer. When the client accepts your quotation, you are committing to deliver the specified work at the specified price. You cannot later charge more unless additional scope is agreed in a variation.

Quotations are used when:

The scope is clearly defined

You want to compete on a fixed price

The client needs budget certainty

You're confident in your pricing and don't want renegotiation later

Language: "this quotation is valid for 30 days," "the quoted price is $2,400 including materials."

A quotation protects the client from price increases and protects you from scope disputes — because everything in and out of scope is defined.

What Is a Proposal?

A proposal is a more comprehensive document that goes beyond price. It typically includes:

Your understanding of the client's problem or need

Your proposed solution and methodology

Deliverables and timeline

Team credentials or case studies

The price or pricing options

Terms and conditions

Proposals are used for:

Complex or high-value engagements

Competitive pitches where you need to demonstrate value, not just price

Consulting, agency, software, or professional service work

Any situation where the "what" and "how" are as important as the "how much"

A proposal without a price is incomplete — it should always conclude with a clear pricing section.

Which One Should You Send?

| Scenario | Document |

|---|---|

| Client asks "how much roughly?" | Estimate |

| Client asks for a firm price on a defined job | Quotation |

| Competitive pitch for a significant engagement | Proposal |

| Simple product or service sale | Quotation |

| Complex consulting or agency work | Proposal |

| Renovation with unknowns | Estimate, then quotation once scope is clear |

The Binding Difference in Practice

If you send a quotation for $5,000 and the client accepts it, you cannot send an invoice for $6,500 unless additional work was agreed in writing. A quotation is a contract.

If you send an estimate for "approximately $5,000," you have more flexibility — but only if you communicate changes promptly and don't present a final bill that's wildly different from the estimate.

Proposals are not necessarily fixed-price commitments — it depends on how they're worded. If a proposal includes a "fee: $X" it's effectively a quotation. If it includes "pricing to be confirmed following discovery phase," it's not.

Converting to an Invoice

In all cases, the document chain leads to an invoice:

Estimate → Scope confirmed → Quotation → Work done → Invoice

Proposal accepted → Work scoped → Quotation or SOW → Work done → Invoice

The invoice should always reference the document that preceded it. "As per accepted quotation Q-2025-031" on the invoice prevents any "I didn't agree to this" response.

In Quotation Expert, you can create quotations and estimates and convert them to invoices in one click — keeping the whole paper trail intact.