There's a specific moment I keep hearing about from other owners: the month your business account stops being scary. You check the balance, and there's more left over than you expected after payroll and the supplier invoices cleared. And then the thought hits — that money is sitting there doing absolutely nothing.
I know that feeling because I lived it. For about eight months, my own company kept a comfortable cushion in a low-interest account because I was too busy running the business to figure out what to do with the cash. When I finally did the math, I'd lost roughly $4,000 in potential returns over those months. Not catastrophic. But not nothing either.
So let's talk about investment strategies for small business owners — not the textbook version, but what actually makes sense when your company is your main asset, your time is zero, and the tax rules are genuinely confusing.
Key Takeaways
- The "best" investment depends on your business stage — pre-profit, stable profit, or excess cash sitting idle
- Keeping cash completely idle lowers your return on assets; even a boring safe option beats it
- Reinvesting in the business is often the highest-return move — but only if you can measure the return
- The 7% rule is a quick inflation-adjustment shortcut, not a promise of returns
- Tax-advantaged accounts for owners (SEP-IRA, Solo 401(k)) matter as much as the investment itself
What actually counts as an investment for a small business owner
Most articles jump straight to stocks and bonds. That's a mistake, because for an owner, there are really two separate pools of money with two different sets of rules. The business's cash, and your personal money. Mixing the two is where people get into trouble — with the tax authorities and with themselves.
Here's the split I use, and I'd argue it's the clearest way to think about it:
- Business capital — money that belongs to the company. Its job is to fund operations, growth, equipment, or short-term reserves.
- Personal capital drawn from the business — money you've taken out (salary, distributions, dividends). Its job is to build wealth outside the company, because your company is already a massive concentrated bet on one thing.
Why idle cash is a real cost, not a safety net
Keeping cash idle feels safe. And a buffer genuinely is safety — I'm not going to pretend otherwise. But there's a difference between a buffer and an excess. When your bank account holds far more than you need for three to six months of operating costs, that surplus is quietly working against you: it lowers your overall return on assets simply by sitting still. Inflation eats at it too, slowly and without drama.
My rule after that $4,000 lesson: I keep a defined reserve (I settled on four months of fixed costs), and anything above that line gets a job. Either it goes back into the business with a measurable purpose, or it gets invested.
Reinvest in the business — but only when you can measure the return
Reinvesting is usually the highest-return option available to an owner, and it's also the most abused. "Investing in growth" is a phrase that covers everything from a genuinely profitable hire to a new software subscription nobody uses.
What changed things for me was forcing every reinvestment decision through one question: what will this return, and by when? Not in a spreadsheet-heavy way. Rough numbers. But numbers.
Three examples of reinvestment that paid off, from my own books:
- A part-time hire for a repetitive task — cost about $1,100 a month, freed up roughly 30 hours of my time, which I redirected into sales. Revenue went up about 12% over the following quarter.
- Equipment upgrade — cut production time per unit by around 20%. Paid for itself in under five months.
- Customer retention work — a simple follow-up system. Churn dropped by about a third. Almost no cash cost, just a week of my attention.
And the failures, because those are more instructive. I once spent $2,600 on a marketing tool that promised automation. I used it for six weeks. It produced nothing I could trace to a sale. The mistake wasn't buying software — it was buying it without defining a success metric first. Now, if I can't write down a single number that would tell me in 90 days whether it worked, I don't buy it.
Real talk: reinvestment is only an "investment" when the return is measurable. Otherwise it's a cost with a nicer name.
Investing company earnings outside the business
Once you've funded operations and the measured reinvestments, the surplus needs somewhere to go. There are several options, and each has tax implications that vary by structure and jurisdiction — so treat the table below as a map, not a set of instructions. Check the specifics for your own situation.
| Option | Liquidity | Typical role | Watch out for |
|---|---|---|---|
| High-yield business savings / money market | Immediate | Reserve above the operating buffer | Returns track interest rates; can be modest |
| Short-term government instruments | Days to weeks | Parking cash for 6–12 months | Lock-up periods, tax on interest |
| Broad diversified funds (held personally) | Days | Long-term wealth outside the company | Market risk; must be personal, not company money |
| Owner retirement accounts (SEP-IRA, Solo 401(k)) | Locked until retirement | Tax-advantaged long-term saving | Contribution limits; early withdrawal penalties |
| Reinvestment in the business | Depends | Growth with measurable return | Unmeasured spending disguised as growth |
Diversify away from your own industry
This one gets repeated everywhere, and it deserves the repetition. If your entire income and your entire net worth both depend on the same sector, you are concentrated in a way that most professional investors would consider reckless. I know owners who put their surplus into more of their own industry — buying into a competitor's supplier, say — because it felt familiar. It isn't diversification. It's doubling down.
Put the surplus where your business isn't.
What is the best investment for a small business?
There's no single answer, and anyone who gives you one without asking about your stage is guessing. The realistic answer depends on where the money sits and what you need it to do.
For company earnings, the sound sequence is: fund a genuine operating reserve, then reinvest in anything with a measurable return, then move the true surplus into liquid, low-risk instruments the business can access if needed. For money you've drawn out personally, the priorities shift toward diversified, long-horizon investments and tax-advantaged retirement accounts designed for owners. The best single move for most owners I've talked to is the boring one: get the excess cash out of the idle account and give it a defined job.
What is the 7% rule in investing?
The 7% rule is a rule of thumb for long-term planning: it assumes an investment grows at roughly 7% per year after inflation, based on the historical long-run behavior of broad stock markets. It's used to estimate how much a sum will be worth decades out, and to work backward from a retirement target.
Two things it is not. It is not a guarantee — actual returns vary widely year to year, and a bad decade is entirely possible. And it is not a business-planning figure; your company's cash needs should never be modeled on stock market assumptions. I use 7% for personal long-horizon planning only, and I use conservative, near-zero assumptions for anything the business might need within two years.
How much do I need to invest to make $10,000 a month?
Assuming the 7% annual growth figure and a standard safe withdrawal rate of about 4% a year, you'd need a portfolio of roughly $3 million to draw $10,000 a month sustainably. At a more aggressive 7% withdrawal assumption, the required figure drops to about $1.7 million — but that pace risks depleting the capital.
The arithmetic is simple; the timeline isn't. A 4% withdrawal on a $3 million portfolio gives you $120,000 a year. Getting there from a standing start takes consistent contributions over a long horizon. Which is exactly why the boring stuff — automating contributions, using tax-advantaged accounts, not touching the money — matters more than picking the perfect fund.
What not to tell investors
If you're raising money rather than deploying it, a few things reliably kill the conversation. Don't tell investors your projections are guaranteed. Don't claim you have no competition — it signals you haven't looked. Don't hide a known weakness in your model, because it will surface in due diligence and it will cost you credibility. And don't present a business plan with no numbers in it; the plan format matters less than whether the figures hold up when someone pushes on them.
Where to start this week
Open your business account and write down one number: the balance above your operating reserve. That's your investment pool. Then split it in two — the portion you can reinvest with a measurable return, and the portion that should be diversified outside your industry. If the second number is bigger than you expected, you already know where your first move is.
The uncomfortable part isn't choosing an investment. It's admitting that the safe-feeling option, the one where nothing moves, is a decision too — and usually the most expensive one.
