Profit Margin for a Service Business: How to Calculate Yours

Profit margin is profit divided by income, times 100. If $9,200 came in and $3,900 was left after expenses, your margin is 42.4%.

It tells you something income alone cannot: how much of each dollar you keep. A business can take in more every month and keep less, and the margin is where that shows first.

Here is the sum, three months of it worked through, and the two versions worth knowing when you are the one doing the work.

Income, expenses and what is left, on one page. Example data.

The short version

• Profit margin = profit ÷ income × 100.

• Work it out for the month and for the quarter. One month alone can mislead.

• Know it twice: before you pay yourself, and after.

• Compare it with your own past months, not with someone else's business.

The sum, step by step

1. Add up everything the business received in the month. That is income.

2. Add up everything the business spent to operate. That is expenses.

3. Income minus expenses is profit.

4. Divide profit by income, and multiply by 100.

Line	Amount
Income	$9,200
Expenses	$5,300
Profit	$3,900
Profit margin	42.4%

So for every dollar a client paid, a little over 42 cents was left once the business had covered its costs.

Three months, side by side

Month	Income	Expenses	Profit	Margin
January	$7,000	$4,900	$2,100	30.0%
February	$9,200	$5,300	$3,900	42.4%
March	$11,500	$6,100	$5,400	47.0%
The quarter	$27,700	$16,300	$11,400	41.2%

Two things to notice. Income rose 64% from January to March, and expenses rose only 24%. That is what a service business with steady costs looks like: once rent, software and insurance are covered, more of each extra dollar stays.

And the quarter's margin is not the average of the three months. It is the quarter's profit over the quarter's income. Always work from the totals.

The two versions every owner should know

If you are a sole proprietor, what you take out of the business is not an expense on your tax return. It comes out of profit. So the figure above is your margin before paying yourself.

That is the right number for tax. It is a flattering number for judging the business, because it treats your work as free.

February	Before your pay	After your pay
Income	$9,200	$9,200
Expenses	$5,300	$5,300
Your pay	not counted	$2,800
What is left	$3,900	$1,100
Margin	42.4%	12.0%

The second column asks a better question: after the business has paid for itself and paid you, is there anything left for tax, for a slow month, for growing? Here there is $1,100, or 12 cents of every dollar.

If that second figure is at or below zero, the business is paying you and nothing else. That is worth knowing before a tax bill tells you. Our post on how to pay yourself as a business owner covers setting that pay figure.

Margin is a trend, so it needs months beside each other. Example data.

What is a good margin?

There is no single honest answer. A consultant working from home and a salon with a lease and product costs are different businesses, and their margins should be different.

The comparison that helps is with yourself. Is this quarter above or below the last one, and do you know why? A margin that slips three months running while income holds steady is telling you that costs are creeping.

Five things that move it

1. Price. A rise in price with the same costs goes straight to margin.

2. Unbilled time. Hours you worked and did not charge for.

3. Subscriptions. Small, monthly, and easy to stop seeing.

4. Discounts. Ten percent off the price can be a quarter off the profit.

5. The mix of work. Some services cost you more to deliver than others.

Three mistakes

1. Using deposits as income. A transfer from your savings or a loan is not income. Count only what clients paid.

2. Leaving out annual costs. Insurance paid once a year still belongs to every month.

3. Judging from one month. A single month catches a big bill or a late payment. Use the quarter.

A fourth, quieter one: working the margin out once and never again. The number matters less than its direction, so put ten minutes in your calendar at the end of each month and write the figure down next to last month's.

Where the figures come from

Margin needs only two totals, and both come from sorted transactions. If your records are a month or more behind, start with the monthly bookkeeping minimum, which takes about an hour.

Start with the whole picture, free

La Soglia, the free membership of the Money Mastery System, holds everything you own and owe in one place, personal and business together, with no bank connection and no card. The Profit and Loss report that gives you income, expenses and profit for any period is part of the paid membership.

Bring it to the Collective

Margins are easier to talk about with people who also run a business on their own. The Money Mastery Collective has a discussion feed open on the free membership.

Questions we hear

How do I calculate profit margin?

Divide profit by income and multiply by 100. Profit is income minus business expenses.

What is a good profit margin for a service business?

It depends on the kind of business and its costs. The useful comparison is your own margin over time.

Does profit margin include what I pay myself?

For a sole proprietor, owner pay comes out of profit. Work the margin out both before and after your pay.

Why did my margin fall when income went up?

Costs rose faster than income. Discounts, new subscriptions and unbilled time are the usual places to look.

References

There are no outside figures in this post. Every number is our own worked example.

Start free with La Soglia

La Soglia is the free membership of the Money Mastery System. It gives you the Net Worth Tracker, where everything you own and everything you owe sits in one place, and the Money Mastery Collective. There is no card to enter and no bank connection.

Start free with La Soglia

Keep in touch

Donna shares a short version of posts like this one on Instagram and LinkedIn. Follow along there, or find everything in one place on our links page.

A note on what this is

This article is educational. The Money Mastery System is an educational tool, not financial software, and nothing here is legal, tax, investment or financial advice. The figures are illustrations, and how owner pay is treated depends on how your business is set up. For guidance on your own circumstances, please speak with a qualified professional who knows them.

How to Tell If Your Business Actually Had a Good Year

Revenue up 20%. Profit down 24%. That is one business, one year, and it is the most common shape of a year that felt good and was not.

$80,000 of revenue at a 22% margin keeps you $17,600. The following year, $96,000 at 14% keeps you $13,440. You worked more, you earned more, and you kept $4,160 less.

Revenue is the number everyone watches because it is the easiest one to see. It is also the only one on this page that cannot tell you whether the year worked.

The Money Mastery System dashboard showing the year against the one before it. Example data.

The short version

• Revenue alone cannot tell you whether the year worked.

• Four checks can: margin, real hourly rate, client concentration, and what the balance is after tax.

• Revenue up and margin down is the most common good-looking bad year.

• A quieter year with a better margin can be the better year.

The four checks

What looked good	What to check instead	What it looks like when the year only looked good
Revenue was up	Profit margin, this year against last	Revenue +20%, margin 22% to 14%, so $4,160 less kept
You were busy all year	Your real hourly rate	Same take-home, 300 more hours worked
You landed a big client	What share of revenue one client is	One client at 40% or more, which is not a client, it is a dependency
The bank balance looked healthy	What of it is the tax set-aside	The balance is the tax money, and it is already spent

Four checks, about twenty minutes, and any one of them can flip the verdict.

How to run them

1. Margin. Profit divided by revenue, this year and last. If revenue rose and margin fell, find out what grew faster than the income did.

2. Real hourly rate. Take-home divided by the hours you actually worked. Our post on your true hourly rate has the grid.

3. Concentration. Your biggest client's revenue as a share of the total. Above 30% is worth a plan. Above 50% is the plan.

4. Set-aside. Subtract what you owe in tax from the balance. What is left is what you actually have.

The year that was good and did not feel it

It goes the other way too, and less is written about it.

A quieter year with a better margin, fewer clients and a proper set-aside is a better year than a loud one that kept less. It rarely feels like it in December, because busy feels like progress and calm feels like risk.

The four checks are the only way to tell those two apart, and neither of them announces itself.

The Profit and Loss screen with this year beside last. Example data.

The margin check, worked through

Margin is profit divided by revenue. In the example at the top, $17,600 divided by $80,000 is 22%, and $13,440 divided by $96,000 is 14%.

The useful question is what the eight points went on. Revenue rose by $16,000. Costs rose by $20,160, from $62,400 to $82,560. So every extra dollar of income arrived with about $1.26 of extra cost attached.

That is the signature of growth bought with discounts, extra help or a bigger space, and it only shows when the two years sit side by side.

What to do with the verdict

If the year passed all four checks, the job is to protect what worked. Write down what changed, and keep it.

If it failed one, that one is next year's single priority, and one is enough. If margin fell, find the cost that grew fastest and price for it. If your real rate fell, reprice or drop the lowest-paying work. If one client is too large a share, win two mid-sized clients before chasing another big one. If the balance is mostly tax, open a set-aside account and move the money the day it lands.

One fix chosen from the numbers beats five resolutions made in January.

Run the four on your own numbers, free

All four come from figures you already have, which is not the same as figures you can reach. La Soglia, the free membership of the Money Mastery System, holds what you own and what you owe in one place, personal and business together, no bank connection and no card. The paid membership is what sorts a year of transactions into the margin figure without you doing it by hand.

Bring it to the Collective

The concentration check is the one people most want a second opinion on. The Money Mastery Collective has a discussion feed open on the free membership.

Questions we hear

What is a good margin?

It varies so much by trade that a single number would mislead you. What matters is your own, this year against last.

What if I do not know my hours?

Track one ordinary week. It is the most useful week of admin you will do all year.

Is one big client always bad?

No. It is only bad unexamined. Know the share, and know what one month without them looks like.

How do I compare years if I only started this year?

Compare halves. The first six months against the second six tells you the direction, which is what the checks are for.

Which check matters most?

Margin, because the other three often explain it. Start there, and use the rest to find out why it moved.

Start free with La Soglia

La Soglia is the free membership of the Money Mastery System. It gives you the Net Worth Tracker, where everything you own and everything you owe sits in one place, and the Money Mastery Collective. There is no card to enter and no bank connection.

Start free with La Soglia

Keep in touch

Donna shares a short version of posts like this one on Instagram and LinkedIn. Follow along there, or find everything in one place on our links page.

A note on what this is

This article is educational. The Money Mastery System is an educational tool, not financial software, and nothing here is legal, tax, investment or financial advice. The figures are worked examples, not a statement about your business. For guidance on your own circumstances, please speak with a qualified professional who knows them.

Self-Employment Tax, Worked Through on $60,000 of Profit

On $60,000 of profit, self-employment tax comes to about $8,478. Half of that, about $4,239, then comes off your income before income tax is worked out.

It is charged on profit, not on everything you were paid. And it is separate from income tax, which is the part that catches people in their first year.

Here is the calculation one line at a time, then the same sum on other amounts so you can find your own.

The Profit and Loss report, where the profit figure comes from. Example data.

The short version

• Self-employment tax is 15.3% of 92.35% of your net profit.

• That works out at about 14.1% of profit at these income levels.

• Half of it is deductible when you work out your adjusted gross income.

• It is on top of income tax, not instead of it.

What is self-employment tax?

It is how people who work for themselves pay into Social Security and Medicare. An employee sees those two taxes taken from every paycheck, and the employer pays a matching amount on top. When you are self-employed there is no employer, so you pay both halves.

That is why the rate looks high the first time you meet it. It is not an extra tax for being self-employed. It is the same contribution, with nobody else paying half.

The calculation, in four lines

Step	What you do	Amount
1	Start with your net profit for the year	$60,000.00
2	Multiply by 92.35%	$55,410.00
3	Multiply by 15.3%	$8,477.73
4	Half is deductible	$4,238.87

Step 1 is profit: what came in, minus what it cost to run the business.

Step 2 trims that to 92.35% of itself. In the IRS's words, "the amount subject to self-employment tax is 92.35% of your net earnings from self-employment."

Step 3 applies the rate. The 15.3% is two taxes together: 12.4% for Social Security and 2.9% for Medicare. On this example that is $6,870.84 and $1,606.89.

Step 4 is the one people miss. You can deduct one-half of your self-employment tax when you work out your adjusted gross income. It does not make the self-employment tax smaller. It makes the income your income tax is charged on smaller.

Where the $60,000 comes from

From your profit and loss: income minus business expenses. Not your deposits, and not your revenue.

This is the most common way the sum goes wrong. Someone who was paid $95,000 and spent $35,000 running the business owes this tax on $60,000, not on $95,000. Working from the bigger number overstates the bill by more than half.

It is also why the monthly labelling matters. Every business expense you record lowers the profit this tax is charged on. An expense you forgot to record is one you pay 15.3% on for no reason.

Your number, at a glance

Net profit	Self-employment tax	Set aside each month
$30,000	$4,238.87	about $353
$45,000	$6,358.30	about $530
$60,000	$8,477.73	about $706
$75,000	$10,597.16	about $883
$90,000	$12,716.60	about $1,060

There is a shortcut hiding in that table. Because 92.35% of 15.3% is about 14.1%, self-employment tax at these levels is about 14.1% of your profit. If your profit so far this year is $20,000, the self-employment tax on it is about $2,826.

Profit to date on the dashboard, the figure the shortcut starts from. Example data.

Who has to pay it

You usually must pay self-employment tax once your net earnings from self-employment reach $400 for the year. That is a low bar, and it catches side income as well as a full-time business.

There is a yearly limit on how much of your earnings the Social Security part applies to. It changes each year and sits well above every figure in the table.

The three most common mistakes

1. Working from deposits. The tax is on profit. Start from what was left after business expenses, never from what arrived in the account.

2. Forgetting the deduction. Half of the self-employment tax comes off your income before income tax. Skip that line and you pay income tax on money the rules let you take off.

3. Treating it as the whole bill. Setting aside 15% and feeling finished is the classic first-year surprise. This tax is one part. Income tax is the other.

None of these is a sign of being bad with money. They come from the sum never having been shown one line at a time.

Month by month

Take a year where profit arrives unevenly: $3,000 in a slow month, $8,000 in a strong one. At about 14.1%, the slow month sets aside about $424 and the strong month about $1,130.

You are not trying to guess the year in January. You are putting away the right share of each month as it happens, so the total is right however the year turns out. For the full set-aside, with income tax included, see our post on how to set your tax set-aside percentage.

Work it out on your own numbers, free

The calculation is four lines. The hard part is line one, your profit to date. La Soglia, the free membership of the Money Mastery System, holds what you own and what you owe in one place, with no bank connection and no card. The paid membership is what turns a year of transactions into the profit figure without adding up statements by hand.

Bring it to the Collective

Whether to keep the set-aside in its own account, and how much, is a good question for the discussion feed. The Money Mastery Collective is open on the free membership.

Questions we hear

Is self-employment tax the same as income tax?

No. Self-employment tax is Social Security and Medicare, worked out on your profit. Income tax is worked out afterwards, on your income after deductions.

Do I pay it if I also have a job?

Yes, on the profit from your own work. An employer withholding from your paycheck does not cover what you earn for yourself.

Can I lower it?

Only by lowering profit honestly. It is charged on profit, so every business expense you record and can evidence reduces it.

When is it paid?

Through the year in estimated payments, then settled on your return. Nobody withholds it for you.

References

The 15.3% rate and its two parts, the 92.35% figure, the $400 threshold and the deduction for one-half are from IRS Tax Topic 554, Self-Employment Tax, updated 24 September 2026, and the IRS Schedule SE instructions. The dollar figures are our own worked examples from those rules.

Start free with La Soglia

La Soglia is the free membership of the Money Mastery System. It gives you the Net Worth Tracker, where everything you own and everything you owe sits in one place, and the Money Mastery Collective. There is no card to enter and no bank connection.

Start free with La Soglia

Keep in touch

Donna shares a short version of posts like this one on Instagram and LinkedIn. Follow along there, or find everything in one place on our links page.

A note on what this is

This article is educational. The Money Mastery System is an educational tool, not financial software, and nothing here is legal, tax, investment or financial advice. The figures are worked examples, not a calculation of your own tax, and tax rules change and depend on your whole situation. For guidance on your own circumstances, please speak with a qualified professional who knows them.