From summer weekends to full time: Brian's tennis coaching business
By Andrew Pham, CPA
TL;DR
Brian turned a high-school and college tennis background plus a wide network of athletes into a private-lessons business that outgrew "summer side gig." We mapped his accounting year over year so he could see the trend rather than one good month, and used that to time the move from W-2 employment to running the business full time. Coaching income is Schedule C: self-employment tax, quarterly estimates, court and travel costs, and a retirement plan you now have to build yourself.
The numbers
- Structure
- Sole proprietor, Schedule C
- Seasonality
- Heavy summer, thinner winter — plan across the year
- Tax lift
- Self-employment tax, quarterly estimates, court and travel costs
- Transition risk
- Losing employer benefits and withholding at once
A network, not an ad budget
Brian played tennis in high school and again in college. That produced something more durable than a trophy shelf: a network of athletes at every age — juniors whose parents want structured coaching, adults returning to the game, competitive players who need a hitting partner who can push them.
He never had to market. Referrals came from people who had already seen him play. That is the pattern behind most coaching businesses that work, and it is why they scale faster than the owner's bookkeeping does.
Summer weekends stopped being enough
It began as summer weekend lessons around a W-2 job. Then weekday evenings. Then a waitlist. At some point he was turning away paying work in order to keep a job that paid less per hour than his lessons did.
That is the moment people call us — and it is also the moment where the wrong decision is expensive in both directions. Quitting too early means losing the cushion. Waiting too long means capping the business.
Mapping the accounting year over year
One good July proves nothing. We built out his numbers across multiple years so the seasonality was visible: what a summer actually contributes, how thin winter runs indoors, whether the trend line is genuinely climbing or just repeating.
With the years side by side, the transition stopped being a leap of faith. He could see the floor — the amount the business produces even in a weak stretch — and compare it against what he actually needs to live on.
What changes when the W-2 ends
Withholding disappears. Coaching income is Schedule C, so income tax and self-employment tax get paid in through quarterly estimates that Brian now has to fund himself.
Deductible costs are real: court and facility fees, equipment and stringing, mileage to lessons and tournaments, certifications and continuing education, liability insurance, scheduling and payment fees. Health coverage and retirement move onto his plate too — and self-employment opens retirement options that can shelter meaningfully more than a typical employee plan.
Why it worked
Nothing here was exotic. He had the skill and the network already. What he didn't have was a picture of his own business accurate enough to make a decision with. Building that picture year over year is the whole job.
How the work went
- 1
Build the multi-year picture
Map income and costs across several years so seasonality and trend are visible instead of averaged away.
- 2
Find the floor
Identify what the business produces in a weak stretch and compare it to actual living needs.
- 3
Fund the tax yourself
Set up quarterly estimated payments and a set-aside rhythm to replace employer withholding.
- 4
Rebuild the benefits
Plan health coverage and a self-employed retirement account before the W-2 ends, not after.
Questions people ask about this one
How do I know when to leave my W-2 for coaching full time?
When the business's reliable floor — not its best month — covers your living costs plus the tax you now owe yourself, and the trend across years is climbing rather than flat. That is a numbers question, and it is answerable.
Are private lesson fees taxable income?
Yes. Coaching and private-lesson income is self-employment income reported on Schedule C, whether paid by cash, check, or app, and whether or not any form is issued.
What can a private coach deduct?
Court and facility fees, equipment and stringing, mileage to lessons and tournaments, certifications and continuing education, liability insurance, scheduling and payment processing fees, and the business share of your phone.
What retirement options do self-employed coaches have?
Options such as a SEP-IRA or a solo 401(k) can allow substantially larger contributions than a typical employee plan, with the right choice depending on your profit and whether you ever hire. Worth modeling before year-end.
Do I need an LLC or S corporation?
Not initially for most coaches. An S corporation election can make sense at higher, stable profit levels, but it adds payroll and filing obligations. It should be a math decision, not a default one.
Discussion
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