Why Do Contractors Mark Up Subcontractors? (And What is Reasonable)
By Fabio Freire, Founder & General Contractor at EZ-Estimates. Published 2026-05-01.
Why Do Contractors Mark Up Subcontractors?
Homeowners ask this. So do new general contractors who have not figured out how to price their own work. The answer is not "greed" — it is the cost of running a construction business that the sub is not paying for.
Here is the breakdown of what GC markup on subs actually covers, what reasonable markup looks like, and why the markup is justified even when it feels high.
The Quick Answer
Most general contractors mark up subcontractors 15-25% on top of the sub's invoice. That markup covers:
- Overhead the sub does not pay for (your office, vehicles, software, insurance)
- Supervision of the sub's work (foreman, project manager, scheduling)
- Coordination with other subs (sequencing, meeting code, fixing handoffs)
- Warranty risk — if the sub disappears, you (the GC) eat the warranty
- Cash-flow risk — you pay subs in 30 days, owner pays you in 60-90
- Profit — running a GC business has to pay you, not just cover costs
The 15-25% is not the GC pocketing free money. It is the cost of being the responsible party.
What the Sub Already Covers
Before the markup discussion, understand what the sub IS pricing into their invoice:
- Their labor (with their own burden — taxes, benefits, comp)
- Their materials at cost-plus (10-30% sub markup)
- Their own overhead (their truck, tools, insurance)
- Their own profit
The sub is already profitable on their invoice. The GC markup is on TOP of that.
What the GC Markup Covers (Detailed)
1. Overhead the Sub Does Not Pay For
A GC operation costs money to run:
- Office or coworking space ($300-2,000/month)
- General liability insurance ($2,000-10,000/year, separate from sub's GL)
- Workers comp on GC employees (foreman, PM, admin)
- Vehicles for the foreman, PM, and yourself
- Software (estimating, scheduling, accounting)
- Bookkeeping and admin time
- Marketing and lead generation
For a $750K/year GC, overhead typically runs $80K-150K. That has to be covered by markup somewhere.
2. Supervision and Project Management
The sub does their work, but someone has to:
- Coordinate when the sub shows up
- Make sure the prior trade finished cleanly
- Answer the sub's questions
- Solve unexpected problems
- Inspect the sub's work
- Coordinate with the next sub
- Communicate with the owner
That supervision is 10-30 minutes per day per sub on a typical residential remodel. Across 5-10 subs and a 6-week job, that is 25-100 hours of GC time.
3. Coordination Between Trades
The order matters: framer before electrician before drywaller before painter before trim carpenter. Each handoff is a coordination point. The GC schedules, follows up, fixes problems, and absorbs delays.
If the framer leaves a wall out of plumb, the drywaller cannot fix it neatly. The GC sends the framer back. The sub bills the GC for the rework. The GC bills the owner via the markup. (Or the GC eats it, which is why markup matters.)
4. Warranty Risk
If the sub does shoddy work and disappears 6 months later, the warranty falls on the GC. The owner does not chase the sub — they call the GC. The GC sends another sub to fix it (often out of pocket).
A typical residential GC has 1-3% warranty cost as a percentage of revenue. On a $200K project, that is $2,000-6,000 of expected warranty work. The markup funds this.
5. Cash Flow Risk
Subs typically demand payment within 30 days of completion. Owners typically pay GCs in 30-60 days from invoice (sometimes 90+ on disputes). The GC floats the cash for 30-60 days.
On a $200K project with $150K in subs, the GC is floating $150K for a month. At 8% cost of capital (line of credit), that is $1,000 in carry cost.
6. Profit
After overhead and risk are covered, the GC needs profit. A healthy GC business runs 8-15% net profit. Below 8% is unsustainable. That profit comes from markup.
What Is "Reasonable" Markup
Industry ranges:
- Residential remodel GC: 15-25% on subs (lower end on materials, higher on labor)
- Custom home builder: 20-30% on subs
- Light commercial: 12-20% on subs
- Heavy commercial: 5-12% on subs (volumes are higher, percentage lower)
- Insurance restoration: 10-20% (insurance often caps "Overhead and Profit" at 10/10)
- High-end residential: 25-40% (white-glove service)
The wider the range, the more competition matters. Your market sets the limits, not your accountant.
How the Markup Math Should Work
Build markup three ways and pick the highest:
Method 1: Flat percentage on subs
- Take sub invoice + 20% (or your number)
- Simple, easy to explain
- Best for repeat clients who trust the relationship
Method 2: Cost-plus
- Bill subs at cost
- Add a separate line item for "GC Overhead and Profit" at 15-25% of total project
- Most transparent
- Best for cost-conscious commercial clients
Method 3: Lump sum (sub markup hidden)
- Bid the whole project as a fixed price
- Markup is built into the price, not exposed
- Best for residential where markup discussions feel awkward
- Standard practice for most residential GCs
Why the Markup Feels High to Homeowners
Homeowners see:
- Sub charges $30K
- GC adds 20% = $36K
- "I am paying $6K extra for nothing"
They do not see:
- The GC's 50 hours of supervision over 6 weeks
- The 2 trips back when the framer left a wall out of plumb
- The warranty risk for the next year
- The GC's overhead allocation
- The cash flow float
When a client questions markup, the answer is not to defend it. The answer is to explain what the markup buys. Most clients calm down once they understand the breakdown.
When Markup Goes Too Far
Markup over 30% on subs is hard to defend in residential. Above 35%, you are asking the client to fund someone's lifestyle. Markets reject this — your competitors will bid 25% and win every job.
The exception: high-end residential where the GC is providing genuine white-glove service (multiple site visits per week, daily client communication, hand-picked subs, premium materials sourcing). In that segment, 30-40% markup is common and reasonable.
What Subs Should Know
If you are a sub, your GC marks up your invoice 15-25%. This is normal. Do not:
- Bill the homeowner directly to "save them money" — this destroys your relationship with the GC and you lose all future work
- Undercut the GC on a side deal — same outcome
- Get angry about the markup — the GC is taking real risk on your work
If you are doing $500K+ of work as a sub through one GC, consider getting your own GC license and bidding direct. Otherwise, accept that the GC markup is the cost of getting consistent work.
What GCs Should Know
Two rules for managing markup transparency:
- Decide your markup ahead of time, in writing. Not "what the market will bear". A consistent markup builds trust over years.
- Do not hide huge markups in lump-sum bids. If the client finds out later, you lose the relationship and any referrals.
Use the construction contract template which has line items for "Subcontractor Total" and "GC Overhead and Profit" separately.
Tools
Stop Underbidding the Markup
EZ-Estimates lets you set markup per line item — labor, materials, subs separately. The AI applies it automatically across every estimate. No more bids that "look profitable" but actually lose money once the sub markup gets compressed.
Free 14-day trial.