How GCs Mark Up Subcontractor Bids: The Math Behind the Number

General contractor (GC) markup on subcontractor bids has no standard rate. It is whatever the contract says. AIA's A201 general conditions set no fixed overhead and profit percentage, so the number is negotiated, and it varies with delivery method, project size and how the contractor separates fee from other costs.

That answer is unsatisfying, so this guide does something more useful. It shows how the layers of a GC price are built, what rules of thumb practitioners quote (and how far to trust them), and which pieces you can negotiate. For the wider context, start with the construction cost estimating guide.

What is GC markup on subcontractor bids, and what does it include?

Most commercial buildings are built largely by subcontractors. The GC collects their bids, adds its own costs and earnings, and presents one price to you. "Markup" is shorthand for the money added on top of the subcontractor's number, and it usually bundles several different things.

• Overhead: the contractor's home-office costs, such as estimators, accounting, office rent and company-wide insurance.
• Profit: what the contractor keeps after covering all costs.
• Fee: in cost-plus and CM-at-risk contracts, the combined overhead and profit figure, stated either as a fixed sum or a percentage of the Cost of the Work (CM stands for construction manager).
• General conditions: the project-specific costs of running the job, covered below.

Part of the confusion in owner conversations is that "markup" can mean any of these, or all of them. Ask your GC to name each layer.

How are the layers of a GC price stacked?

A bid from a GC is rarely a single multiplication. It is a build-up. The table shows the usual order, with who controls each line.

General conditions are often a capped lump sum or a monthly or daily rate rather than a percentage, according to the Georgia and Greenville County school contract forms cited. That matters because a contractor who prices general conditions low and fee high can look cheaper on the line you compare, while costing the same in total.

What markup percentages do people quote, and can you trust them?

Treat all quoted percentages as rules of thumb. There is no authoritative US benchmark for a typical GC markup on subcontractors. What exists is practitioner and vendor commentary.

• Practitioner sources cite roughly 5-10% combined markup on subcontracted work and 10-15% overhead and profit on change orders. Buildern summarizes these as rules of thumb, and they are not market standards.
• One institution's published template, the University of West Florida's CM-at-risk exhibit, shows an overhead and profit fee of 5.5% alongside a 2.5% CM-managed contingency. That is one owner's form, not a market benchmark.
• Contractor profitability data also circulates, such as net margins of 5-10% on commercial work from Projul, but net margin and markup are different measures. A 7% net margin does not imply a 7% markup.

Use these figures to calibrate a conversation, not to judge a bid. A GC quoting a number outside the range is not necessarily overcharging; it may have moved costs into another line.

Why is markup on subcontractor work not the same as the GC's profit?

A markup is applied to revenue, and profit is what remains after costs. A GC that adds a markup to subcontractor invoices still has to pay for its project staff, home office, insurance, bonding, and the risk that a subcontractor defaults or a scope gap appears.

Illustrative example: a GC receives subcontractor bids totaling $4,000,000 on a project and applies a 6% combined markup. The markup is $4,000,000 x 0.06 = $240,000. If the GC's home-office cost allocated to that job is $140,000, the remaining $100,000 is the profit before tax, or 2.4% of the subcontracted cost. These figures are assumptions for arithmetic only, not market data.

The takeaway: a markup that looks large to an owner can be mostly overhead. Pushing the percentage down without understanding the build-up usually shifts cost somewhere else, or pushes the contractor to cut staffing.

What parts of GC markup can an owner negotiate?

Quite a lot, and mostly before signing. After award, leverage is thin.

1. Fee structure. A fee can be a fixed sum or a percentage of the Cost of the Work. A fixed fee removes the incentive to grow cost. A percentage fee scales with scope changes.
2. Fee base. Owners often exclude items such as insurance from the base the percentage is applied to, according to law-firm commentary in Pillsbury's Construction Fee Factors. That commentary is summarized from search results, so confirm with your attorney.
3. Change-order markup. Set the rate in the agreement. AIA guidance notes that A201 sets no fixed percentage, and that on a net decrease the owner's credit is the actual net cost, with the contractor keeping overhead and profit tied to removed work. Know that rule before you delete scope.
4. Dead band. You can negotiate a threshold under which early change orders carry no fee.
5. Subcontractor tiers. Ask whether the markup applies to a subcontractor's own sub-subcontractors, which stacks markup on markup.

What does a full price build-up look like?

Illustrative example: a 40,000 SF two-story medical office building in Phoenix, with assumed round numbers to show the arithmetic. Every figure below is an assumption, not market data.

Now change one rule. If the contract excludes the $150,000 of insurance and bond from the fee base, the fee falls to 4% of $8,300,000, or $332,000. The $6,000 difference is small here, but on larger projects with larger pass-throughs it grows. The point is that the same 4% can produce different dollars depending on what the percentage touches.

Also note that the fee as a share of the subcontractor number alone is $338,000 / $7,000,000, or about 4.8%. The same fee can be described as 4% or 4.8% depending on the denominator, which is why asking "4% of what?" matters before you compare bids.

How should you compare two GC bids with different markups?

Normalize first, then compare. Put both bids into the same layers from the table above. If one bid shows a 4% fee and another 6%, check whether general conditions, insurance, bond and contingency sit inside or outside that fee. See the construction budget breakdown for a line-by-line structure.

Also confirm what the markup applies to. A percentage on a low subcontractor number that later grows through change orders can cost more than a higher, fixed fee. The allowances versus lump sum article explains how pricing mechanisms shift risk, and the overhead and profit explainer covers what a fair margin looks like from the contractor's side.

What are the red flags in a GC's markup?

• A markup number with no breakdown of general conditions, insurance, bond or contingency.
• A percentage fee applied to every line, including pass-through insurance.
• Change-order markup that is not stated in the agreement.
• A very low fee paired with a high, uncapped general-conditions line.
• Reluctance to show subcontractor buyout results in a cost-plus or GMP contract.

One honest caveat: nothing here replaces a project-specific review. Markup norms differ by market, delivery method and the contractor's backlog, and your attorney should read the fee language before you sign.