Guide

How to Write a Construction Bid: Line-Item Structure and a Template

By Curtis Holder, BidCraft · Last updated September 30, 2026

A construction bid is a written offer to perform a defined scope of work for a stated price under stated terms. Once the client accepts it — usually by signing it or a contract that incorporates it — it is the backbone of the deal. A good bid is easy to compare, hard to misread, and priced from a real takeoff rather than a gut number.

1. Before you price anything

• Read every document. Drawings, specifications, the bid form, and every addendum. Note which addenda you received; many bid forms ask you to acknowledge them by number.
• Walk the site. Access, staging space, existing conditions, utilities, and anything the drawings don't show. Photograph what you see.
• Ask questions in writing. If something is ambiguous, send a request for information (RFI) before the deadline instead of guessing. On a private job with no formal RFI process, email the client and keep the answer.
• Get sub and supplier quotes early. Give every subcontractor the same scope description so their numbers are comparable, and note what each quote includes and excludes.

2. Do the takeoff

A quantity takeoff measures what the job needs: square feet of drywall, linear feet of trim, cubic yards of concrete, fixture counts, and so on. Price from quantities, not from a lump guess. Add a waste factor appropriate to each material and trade, and record the assumption so you can defend or adjust it later.

3. Structure the bid

Most solid bids contain the same parts, whatever the trade:

1. Header. Your company name, address, phone, email, and license number where your state requires it; the client's name; the project name and address; the bid date; and a bid number.
2. Scope summary. Two or three sentences stating what you will do, referencing the drawings and specifications (with dates or revision numbers) the price is based on.
3. Line items. The priced breakdown (see below).
4. General conditions. Job-specific costs that aren't tied to one task: supervision, temporary facilities, dumpsters and haul-off, equipment rental, permits and fees if you are responsible for them, cleanup.
5. Overhead and profit. Your company costs and margin, shown either as a line or built into unit prices.
6. Allowances and alternates. Amounts carried for items not yet selected, and priced options the client can accept or decline.
7. Exclusions and assumptions. What is not included, and the conditions your price depends on.
8. Schedule. Expected start, duration, and any dependencies (for example, owner selections or permit approval).
9. Terms. Payment schedule, change-order process, warranty, and how long the price is valid.
10. Acceptance. A signature block for the client.

4. Write the line items

Each line should let the client (and you, six weeks later) see exactly what was priced. A useful line item has:

• a description specific enough to check — "Install 1/2 in. drywall, walls, Level 4 finish," not "Drywall";
• a quantity and unit (SF, LF, CY, EA, LS);
• a unit cost, split into labor, material, and equipment where that helps;
• an extended cost (quantity × unit cost).

Group lines by trade or phase. Commercial work is often organized by CSI MasterFormat divisions (for example 03 Concrete, 06 Wood, Plastics and Composites, 09 Finishes); residential bids more often follow the order the work happens (demolition, framing, rough-in, insulation, drywall, finishes). Pick one scheme and use it consistently so bids are easy to compare.

How much of the breakdown you show the client is a business decision. Many contractors show quantities and line totals but keep unit costs and markup internal. Either way, build the number from the detail.

5. Overhead, profit and contingency

• Overhead is the cost of running the company — office, insurance, vehicles, software, non-billable staff — spread across jobs. Know your own number; don't borrow someone else's percentage.
• Profit is what you keep after all costs. It pays for risk and growth.
• Markup and margin are different. Markup is a percentage of cost; margin is a percentage of the selling price. Marking up $100 of cost by 20% gives a $120 price, which is a margin of about 16.7% ($20 ÷ $120). Confusing the two is a common way to underprice.
• Contingency covers the known unknowns in your own work — say, rot you expect behind old siding. Decide whether you carry it in your price or disclose it as a separate line with rules for how it is used.

6. Allowances, alternates and exclusions

An allowance is a placeholder amount for something not yet chosen, such as light fixtures or tile. State what the allowance covers (material only, or material and installation) and that the final price adjusts up or down to the actual selection.

An alternate is a separately priced option — a different roofing material, an added deck — that the client can accept or decline without re-bidding.

Exclusions protect both sides. Typical examples: permits and fees (if the owner pulls them), engineering, hazardous-material testing or abatement, work behind walls not visible at the walkthrough, landscaping repair, and owner-supplied items. Be specific — "unforeseen conditions" alone invites an argument.

7. Terms that prevent disputes

• Payment schedule tied to milestones (for example, deposit, rough-in complete, drywall complete, substantial completion, final). Deposits on residential work are limited by law in some states; check your state's rules.
• Change orders: no extra work without a written, priced, signed change order.
• Bid validity: how long the price holds. Many contractors use 30 days and shorten it when material prices are volatile.
• Warranty: what you warrant and for how long, separate from manufacturer warranties.
• Lien waivers on payment if they are customary in your market.

8. Construction bid template

Copy this outline into your own letterhead. The figures in the sample rows are illustrative arithmetic only, not a price guide.

[Company name] · [Address] · [Phone] · [Email] · License # [number]

BID / PROPOSAL #[number]                     Date: [date]
Client: [name]           Project: [name, address]
Based on: [drawing set, revision/date], [specification, date], Addenda [#s]

SCOPE SUMMARY
[Two or three sentences describing the work.]

LINE ITEMS
Item  Description                                   Qty   Unit  Unit cost  Extended
01    Demolition — remove existing vanity & tile     1    LS    [ ]        [ ]
02    Drywall — 1/2 in., walls, Level 4 finish     400    SF    $2.50      $1,000.00   (illustrative)
03    Tile — floor, set & grout (material by owner) 60    SF    [ ]        [ ]
...
      General conditions (supervision, dumpster, cleanup)         [ ]
      Overhead & profit                                           [ ]
      TOTAL                                                        [ ]

ALLOWANCES     [Item] — $[amount], material only; final price adjusts to selection
ALTERNATES     Alt 1: [description] — add $[amount]
EXCLUSIONS     [Permits and fees / engineering / hazardous materials / ...]
ASSUMPTIONS    [Working hours, access, owner selections due by (date), ...]
SCHEDULE       Start [date or "within X days of signed contract"]; duration [X] working days
PAYMENT        [Deposit]; [milestone payments]; final on completion
CHANGES        Written, priced change orders signed before extra work begins
WARRANTY       [Terms]
VALIDITY       This price is valid for [X] days from the date above.

Accepted by: ____________________   Date: __________

9. Common mistakes

• Pricing from the drawings without walking the site.
• Missing an addendum, or not listing the documents the price is based on.
• Vague line items ("Electrical — $X") that can't be compared or defended.
• Forgetting general conditions such as disposal, protection, and cleanup.
• Treating markup as margin.
• No exclusions, no bid-validity date, no change-order clause.

Drafting a bid with BidCraft

BidCraft's free Quick Bid turns a project description into a draft line-item bid with a scope of work — one free draft per email, no account. Inside the app, the AI Bid Builder walks through project, scope, materials, labor and margins, then generates a bid document you can send to a client as a share link. Treat any AI draft as a starting point: check quantities, pricing and scope against your own takeoff and local costs before it goes out.