Why Your 25% Markup Only Gives You 20% Profit (And How Bad Math is Bleeding Your Jobs Dry)
Picture this: You’re on a job site watching your concrete crew mix their first batch of the day. The new guy grabs the water hose and starts eyeballing the ratios. “Close enough,” he shrugs, dumping in what looks right. You know that concrete will pour just fine today, but in six months, when cracks start spider-webbing across that foundation, “close enough” becomes a very expensive lesson.
The same thing happens when contractors eyeball their markup math. You’ll win bids, pour projects, and collect checks. Everything looks solid on the surface. But deep down in your financials, profit cracks are already forming. Most contractors think slapping a 25% markup on their costs delivers 25% profit. The brutal truth? That 25% markup only puts 20% in your pocket — and that 5% gap is bleeding jobs dry across America.
This isn’t some accounting theory cooked up in a classroom. It’s real money walking out the door of real construction companies every single day.
The $131,000 Kitchen Remodel Mistake
Let me tell you about Sarah, a residential remodeler pulling in $1.2 million annually. Sharp contractor, great reputation, beautiful work. She thought she was crushing it with 30% profit margins on every kitchen remodel.
Here’s where the concrete started cracking: Sarah was adding 30% markup to her costs, assuming that delivered 30% margin. The real math? Her 30% markup only delivered 23.1% margin — a shortfall of nearly 7 percentage points per job.
On her typical $80,000 kitchen remodel, that gap cost her $5,600 per project. Sarah cranks out about 15 kitchens a year, which means she was throwing away $84,000 annually in profit that should have been sitting in her bank account. Over three years, that’s a quarter-million dollars that vanished because of bad markup math.
Think Sarah’s case is extreme? I see this every week. Contractors bleeding five and six figures annually because they never learned the difference between markup and margin.
The Real Math Behind Markup vs. Margin (It’s Simpler Than You Think)
Here’s the foundation every contractor needs to understand:
Markup = the percentage you add on top of your costs to get your selling price
Margin = the percentage of profit compared to your final selling price
They’re not the same animal, and treating them like twins will cost you serious money.
Let’s run some back-of-the-napkin math:
- Job costs: $10,000
- Add 25% markup: $10,000 × 1.25 = $12,500 selling price
- Your profit: $2,500
- Your actual margin: $2,500 ÷ $12,500 = 20%
See the problem? You marked up 25% but only got 20% margin. To actually hit 25% margin, you’d need to markup 33.3%.
Want to nail 30% margin like Sarah thought she was getting? You need 42.9% markup, not 30%. Most contractors’ jaws hit the floor when they see these numbers, but the math doesn’t lie.
The $85,000 Per Job Disaster That Nearly Sank a Company
Here’s a war story that’ll make your stomach turn. Commercial contractor running a tight ship with two solid estimators — let’s call them Mike and Dave. Both guys had been estimating for years, winning bids, keeping the company busy.
But something was off. Mike’s jobs consistently made money. Dave’s projects… not so much. Same company, same overhead, same labor rates. The difference was driving the owner crazy.
It took two years to figure out the problem: Mike was using markup percentages correctly. Dave was treating markup like margin. On paper, their bids looked similar. In reality, Dave was systematically underbidding every job by 5-10%.
The breaking point? A $4.2 million commercial project where Dave’s math error created an $85,000 shortfall. One job, eighty-five grand in missing profit. The annual damage from Dave’s confusion? Nearly $100,000 in lost profit the company never saw coming.
That’s the thing about markup mistakes — they compound. Every bid, every job, every year. Like a slow leak in your hydraulic line, you don’t notice it until your excavator stops moving.
The Profit First Connection: Bad Math Breaks Everything
This isn’t just about profit margins looking pretty on your WIP reports. When you bid with wrong markup math, you’re poisoning every bucket in your Profit First system.
Remember, Real Revenue equals Revenue minus JobEx (your direct job costs: subs, materials, equipment, bonds, permits). When you underbid due to markup confusion, that Real Revenue shrinks fast. Suddenly:
- Your overhead allocation is too thin
- Owner compensation gets squeezed
- Tax reserves fall short
- Profit accounts never fill up
You might show profit on paper, but where’s the cash? The goal isn’t theoretical margins — it’s actual money in the bank. Wrong markup math means you’re fighting for cash flow instead of building wealth.
It’s like trying to frame a house with wet lumber. Sure, you can get the walls up, but when everything starts warping and twisting, you’ll be back fixing problems instead of building the next project.
The Simple Fix Every Contractor Needs (And Why Most Don’t Use It)
Here’s the good news: fixing this problem takes about ten minutes and a simple chart.
Create a standardized markup table and tape it to every estimator’s desk. When they need 25% margin, the chart shows them to markup 33.3%. Want 30% margin? Markup 42.9%. No guesswork, no confusion, no $85,000 mistakes.
The formula is dead simple: Selling Price = Cost ÷ (1 – Desired Margin)
Want 20% margin on a $10,000 job? $10,000 ÷ (1 – 0.20) = $10,000 ÷ 0.80 = $12,500
But here’s the rub: most contractors never implement this fix because they think they’ve got it handled. “I’ve been bidding jobs for twenty years,” they say. Meanwhile, twenty years of markup confusion has cost them enough money to buy a lake house.
The golden rule to remember: Margin is always less than markup. Always. If someone tells you to “markup 25% for 25% profit,” they’re either confused or selling you something.
Stop the Bleeding, Start Building Wealth
Every day you bid jobs with wrong markup math is another day profit walks out the door. That money should be building your retirement account, funding equipment purchases, or sitting in reserve accounts for the next economic downturn.
Think about Sarah’s $84,000 annual loss. That’s a new truck every year, or a down payment on commercial real estate, or college tuition for her kids. Instead, it vanished into the gap between what she thought she was making and what she actually earned.
The fix is right in front of you. Build the markup table, train your estimators, and stop treating profit like a suggestion. Your future self — and your bank account — will thank you.
Remember: In construction, close enough gets people hurt. In bidding, close enough gets you broke.
Ready to plug the profit leaks in your construction business? Watch the full episode on Youtube, listen on Spotify, or download on Apple Podcasts.
For help implementing Profit First principles in your construction company, book a call.