Most coaches I know are great at helping kids get better. But when it comes to self-employed retirement plans, we tend to shrug and say, “I’ll figure that out later.”
Here’s the problem: “later” turns into years. And you end up paying more tax than you should, while your future self gets nothing.
If you’re thinking about retirement for personal trainers or private coaches, the big question usually becomes: SEP IRA vs solo 401k—which one fits your business right now? Let’s break it down in plain words, with real numbers, so you can stop leaving the self-employed tax advantage on the table.
Background: How self-employed retirement plans work (and why coaches miss out)
When you work for a school or gym, they might offer a 401(k). When you’re on your own—private sessions, small groups, camps, online coaching—you have to set up your own plan.
The good news: the IRS gives self-employed people some of the best retirement tools out there. The bad news: nobody explains them in coach language.
Here are the three most common options for independent coaches and trainers:
- SEP IRA: Simple to open. Simple to run. You can often put in a good chunk of your profit. No Roth option.
- Solo 401(k) (also called an “individual 401(k)”): More moving parts, but usually lets you save more—especially once your income climbs. Often has a Roth option. Some plans allow loans.
- SIMPLE IRA: A “starter” plan if you have employees. Lower limits than a solo 401(k). Easier than a full 401(k).
A few basics you need before we compare:
“Net earnings” is what matters (not your gross sales)
If you bring in $120,000 in revenue but you spend $40,000 on rent, ads, equipment, software, and insurance, you don’t have $120,000 to work with. You have profit.
Retirement plan limits for self-employed people are based on net earnings from self-employment (your profit), with a specific IRS adjustment for self-employment tax. (This is why your CPA or tax software matters.)
Traditional vs Roth (simple version)
- Traditional contributions usually lower your taxable income today.
- Roth contributions usually do not lower taxes today, but can come out tax-free later (if rules are met).
If you want the option to do Roth, that pushes you toward a solo 401k.
Official IRS starting points (worth bookmarking):
- IRS overview of retirement plans for small businesses: https://www.irs.gov/retirement-plans/plan-sponsor/small-business-retirement-plans
- SEP IRA basics (IRS): https://www.irs.gov/retirement-plans/sep-plans
- One-participant (solo) 401(k) basics (IRS): https://www.irs.gov/retirement-plans/one-participant-401k-plans
Main Content 1: SEP IRA (simple, solid, but capped by your profit)
A SEP IRA is the “keep it simple” choice. If your coaching business is just you (no employees), and you want something you’ll actually follow through on, a SEP is hard to beat.
Why coaches like a SEP IRA
- Easy setup: You can open one at places like Vanguard, Fidelity, Schwab, or many banks.
- Low admin: Usually no annual filing forms for the plan.
- Flexible funding: You can decide how much to contribute each year (or skip a year).
- Good tax break: Traditional SEP contributions generally reduce taxable income.
The big SEP IRA limit (the part most people misunderstand)
A SEP IRA contribution is based on a percentage of your net self-employment earnings. People hear “25%” and assume it’s always 25% of profit.
Real-life coaching version:
- For a self-employed person, the effective max rate often works out to about 20% of net earnings, because of how the IRS calculates it with self-employment tax adjustments.
So if you net $80,000, your max SEP contribution is often around $16,000 (give or take), not $20,000. Your tax pro can run the exact number.
SEP IRA example (simple math)
Let’s use clean numbers so you can see the idea.
Coach A nets $40,000 from private sessions and camps.
- Rough SEP max (rule-of-thumb): ~20% of $40,000
- Estimated SEP contribution: ~$8,000
If you’re in a 22% federal tax bracket, an $8,000 contribution could save around:
- $8,000 × 22% = $1,760 in federal income tax (state tax could add more savings)
That’s real money.
Where SEP IRAs can bite you
- No Roth SEP IRA. It’s pre-tax only.
- If you have employees, you must contribute for them too, using the same percentage you give yourself.
- Example: If you contribute 15% for yourself, you may need to contribute 15% of eligible pay for each eligible employee.
- Lower ceiling than solo 401(k) at mid-to-higher incomes. Once you’re doing well, the SEP can leave savings on the table.
If you’re still building and want the simplest “do it this week” plan, a SEP IRA is often the best first step.
Main Content 2: Solo 401k (higher limits, Roth option, best once income climbs)
A solo 401k is built for a business with no employees (other than a spouse, in some cases). This is the plan many full-time private coaches end up using because it can unlock bigger contributions.
Why solo 401k contributions are usually higher
A solo 401k lets you contribute in two roles:
- Employee contribution (you, the worker)
- Employer contribution (you, the business owner)
That “two-bucket” setup is the magic.
Current-year limits (use these as your planning numbers)
For 2026, the employee contribution limit is $23,500 (plus an extra catch-up amount if you’re age 50+). The total limit (employee + employer combined) is $70,000 (not counting catch-up). These numbers adjust over time.
Official source for 401(k) limits: IRS 401(k) resource page (includes annual updates):
https://www.irs.gov/retirement-plans/401k-plans-deferrals-and-matching-when-compensation-exceeds-the-annual-limit
Solo 401k example: why it beats a SEP at $80K+ net
Let’s compare on net earnings of $80,000.
SEP IRA (rule-of-thumb): ~20% × $80,000 ≈ $16,000
Solo 401k:
- Employee bucket: up to $23,500
- Employer bucket: roughly ~20% of net earnings (rule-of-thumb) ≈ $16,000
- Total possible (rough estimate): $23,500 + $16,000 = $39,500
That’s a huge gap.
Even if the exact employer math changes a bit with your taxes, the pattern is the same:
- SEP is one lever
- Solo 401k is two levers
Other solo 401k perks coaches care about
- Roth option (in many plans): Great if you want tax-free growth later.
- Loans (in some plans): Not my favorite move, but it can be a safety valve.
- Clear “owner plan” structure: Fits a one-person training business.
The solo 401k downsides (be honest)
- More admin: More setup choices. More rules.
- Annual filing once big enough: If plan assets go over a threshold (commonly $250,000), you may need to file Form 5500-EZ each year.
- Not for businesses with employees: If you hire staff coaches (not counting spouse in some cases), you may need a different plan.
If you’re consistently netting above about $60,000, a solo 401k is often the best tool for retirement for personal trainers and private coaches who want to save aggressively.
Practical Examples: contribution math for $40K, $80K, and $120K net (coach scenarios)
Let’s put real coaching situations to this. These are simplified examples to show direction. Your exact limit depends on how your business is set up (sole prop vs S-corp), and your real tax numbers.
Scenario 1: New personal trainer, $40,000 net (side hustle turning serious)
You train clients 4 evenings a week and run one weekend small group.
- Net earnings: $40,000
Option A: SEP IRA
- Estimated max: ~20% × $40,000 = $8,000
Option B: Solo 401k
- Employee: up to $23,500 (but you may not be able to afford that yet)
- Employer: ~20% × $40,000 = $8,000
- Realistic contribution if cash is tight:
- Employee: $200/month = $2,400/year
- Employer: $3,000 at year-end
- Total: ~$5,400
Coaching takeaway: At $40K net, the SEP is simple and strong. The solo 401k is great if you want Roth and flexibility on the employee side.
If you’re still fixing pricing, check our guide on setting coaching rates with confidence so you can actually fund the plan.
Scenario 2: Full-time private coach, $80,000 net (steady pipeline, busy schedule)
You do:
- 25 private sessions/week at $75 = $1,875/week
- 2 small groups/week (6 athletes at $25) = $300/week
That’s about $2,175/week before expenses. After expenses, you net $80K.
SEP IRA
- Estimated max: ~20% × $80,000 = $16,000
Solo 401k
- Employee: up to $23,500
- Employer: ~20% × $80,000 = $16,000
- Estimated total: $39,500
Tax impact example (simple):
- If you contribute $39,500 pre-tax and you’re in a 24% bracket, that’s roughly:
- $39,500 × 24% = $9,480 less federal income tax (rough estimate)
That’s why I say coaches leave money on the table. This isn’t “finance talk.” This is cash you can keep.
If your schedule is chaos, you’ll also want a clean system so you can track income and plan contributions. Our article on setting up booking and scheduling for private training helps a ton.
Scenario 3: High-earning trainer/coach, $120,000 net (camps, teams, online add-ons)
You run:
- Off-season program packages
- Summer camps
- A few team contracts
- Some online training
SEP IRA
- Estimated max: ~20% × $120,000 = $24,000
Solo 401k
- Employee: $23,500
- Employer: ~20% × $120,000 = $24,000
- Estimated total: $47,500
That extra ~$23,500 you can shelter (vs SEP) is a big deal.
Where SIMPLE IRA fits (and why it’s usually “Plan B”)
A SIMPLE IRA is often used when you have employees and want something easier than a full 401(k). But the limits are lower than a solo 401k, and you must make certain employer contributions.
In coach terms:
- If you’re truly solo: SIMPLE usually isn’t your best move.
- If you have 1–5 part-time coaches helping and you want a straightforward plan: SIMPLE can be a decent middle step.
Official SIMPLE IRA overview (IRS):
https://www.irs.gov/retirement-plans/simple-ira-plans
Want to understand your real business profit first? Start with the true cost of running a private coaching business so your “net” number is real.
Common mistakes and misconceptions (what trips coaches up)
-
“I’ll start when I make more.”
Starting with $100/month beats waiting two years. -
Confusing revenue with profit.
Your plan limits are based on net earnings, not what Stripe deposits. -
Assuming SEP is always 25% of profit.
For many self-employed coaches, it’s closer to ~20% after the IRS formula. -
Opening the account but never funding it.
Automate a monthly transfer, even if it’s small. -
Hiring help and accidentally breaking the solo 401k rules.
Once you have employees who meet eligibility rules, you may need a different plan. -
Not coordinating with your tax plan.
Your retirement plan choice should match how you file taxes. If you haven’t read it yet, our complete tax guide for private coaches and trainers is the foundation.
Step-by-step: how to choose and open a SEP IRA or solo 401k (coach-proof)
Here’s a simple playbook you can run this week.
Step 1: Get your real net income number
- Look at last year’s tax return, or your year-to-date bookkeeping.
- Write down your estimated net self-employment earnings.
If you don’t track well yet, fix that first. Even a basic spreadsheet helps.
Step 2: Pick the plan based on your situation
Use this quick filter:
-
Choose a SEP IRA if:
- You want the simplest setup
- You’re under ~ $60,000 net (or you just want “easy”)
- You don’t care about Roth contributions
- You don’t have employees (or you understand the employee rule)
-
Choose a solo 401k if:
- You net around $60,000+ and want higher limits
- You want a Roth option
- You want the option of a plan loan (not always recommended, but possible)
- You have no employees (besides a spouse, in some cases)
-
Consider a SIMPLE IRA if:
- You have employees and want a simpler plan than a full 401(k)
- You’re okay with lower limits
Step 3: Decide where to open it
Most coaches open these at:
- Vanguard
- Fidelity
- Charles Schwab
- E*TRADE (also common for solo 401k)
When you compare providers, look for:
- Low fees
- Good index fund options (simple, diversified funds)
- Roth solo 401k availability (if you want Roth)
- Loan option (if you care)
- Ease of making contributions
Step 4: Set a contribution plan you can stick to
A good “coach budget” approach:
- Monthly auto-contribution: 5%–10% of net income
- Quarterly check-in: adjust based on season (busy summer, slower winter)
- Year-end top-off: add more if cash is strong
Example:
- Net $80,000/year ≈ $6,667/month
- 8% monthly = about $533/month
- Then add a year-end lump sum if you can.
Step 5: Coordinate with your tax pro before you file
Tell them:
- Which plan you opened
- How much you contributed
- Your business structure (sole prop, LLC, S-corp)
This is how you make sure you get the deduction right and don’t overfund.
Step 6: Put it on your “business owner calendar”
Every year, set reminders for:
- Contribution planning (mid-November)
- Final numbers (January–March)
- Filing needs (especially if solo 401k assets get high)
Key takeaways / Bottom Line (SEP IRA vs solo 401k for coaches)
If you’re serious about building wealth, retirement isn’t optional. It’s part of running a real coaching business.
- A SEP IRA is the simplest of the main self-employed retirement plans. It’s great if you want easy and flexible.
- A solo 401k usually wins once you net around $60,000+, because you can often save a lot more using the employee + employer buckets. It may also offer Roth and loans.
- A SIMPLE IRA can work if you have employees and want something straightforward, but it has a lower ceiling.
Pick a plan you’ll actually fund. Then automate it like you automate client reminders. Your future self will thank you.