St. Louis Small Business Guide: 5 Common Bookkeeping & Accounting Mistakes
As a St. Louis small business owner, you wear a lot of hats. Bookkeeping and accounting often get pushed to the bottom of the list — but neglecting your financials can lead to costly mistakes, higher taxes, or even IRS trouble. After more than a decade helping businesses in St. Louis clean up their books, here are the five most common bookkeeping and accounting mistakes I see — and how to avoid them.
1. Data Entry Errors (and the Myth of Doing It All Yourself)
Owning a business doesn’t mean you have to know everything — and accounting is one area where “you don’t know what you don’t know” can cause real problems.
Many business owners try to do their own books to save money, but small mistakes in QuickBooks, Sage, or other systems often snowball into bigger issues. Inaccurate financials can lead to:
Higher taxes than you should be paying.
Trouble qualifying for loans.
Costly IRS audits.
And here’s the kicker: once an accountant has to step in, it usually costs more to untangle the mess than if the books had been set up right in the first place. Doing your own books may seem cheaper upfront, but it often creates bigger headaches down the road.
2. Falling Behind on Bookkeeping
Let’s face it: bookkeeping is time-consuming and not exactly exciting. For most St. Louis business owners, it’s the last thing you want to deal with when you’re busy running day-to-day operations.
The truth is, discipline is the hardest part of bookkeeping. As business owners, we naturally want to focus on the parts of the business that bring in money. But falling behind on your books is a costly mistake. It makes year-end overwhelming, creates blind spots in your finances, and drives up CPA fees because they’ll spend more time cleaning things up.
If you’re determined to do your own bookkeeping, the best approach is consistency. I recommend setting aside time once a week — say, a Saturday evening — to update your books. Keeping the work manageable and bite-sized is far less painful than tackling months of backlog all at once.
3. Mixing Personal and Business Accounts
This one seems obvious, but it’s one of the most common mistakes I see. Business and personal expenses should always remain separate.
Mixing accounts doesn’t just make bookkeeping messy — it also leaves you vulnerable to potential liabilities, especially if you’re structured as an LLC or corporation. Commingling funds can blur the legal line between you and your business, which is exactly what you don’t want if you ever face a lawsuit or IRS scrutiny.
It also gives the IRS room to dig deeper if an audit does occur. Even if your financials are otherwise clean, mixing accounts can make you look less credible in the eyes of regulators and lenders.
Now, this doesn’t mean you can’t use a credit card in your personal name as your business card — many owners start that way. The key is discipline: once you designate that card for business, it should be used only for business expenses going forward. Keeping those lines clean will save you time, money, and risk.
4. Not Keeping Your Accountant in the Loop
I get it — keeping your accountant in the loop can feel a little like having a chaperone when you’re in your 20s. You’d rather just handle things yourself. But here’s the truth: proactively talking with your accountant helps them understand what you’re planning and where you want to be.
That context means we can do more than just prepare reports — we can actually advise and strategize with you. Regular check-ins lead to smarter tax planning, better cash flow, and fewer surprises.
January 1st and April 15th aren’t the only times you should talk to your accountant. If you wait until tax season, it’s often too late to make changes that could save you money. Talking throughout the year gives your accountant the chance to guide you, not just react after the fact.
5. Misunderstanding Your Financials
The profit and loss statement is the starting point of financial literacy — but it’s also one of the most commonly misunderstood reports. The reason? Not everything shows up on it.
Items like credit card payments, loan principal payments, and owner’s draws aren’t reflected on the P&L (IRS overview). This often leads business owners to believe they’re profitable when, in reality, they’re cash poor — or worse, cash flow negative.
That’s where an experienced accountant with a background in operational cash flow makes the difference. We cut through the numbers to get to the heart of your business. With the right guidance, you’ll make better decisions, grow at a sustainable pace, and strengthen your position with lenders — along with many other benefits that ripple through every part of your operations.
Avoiding Mistakes Starts Here
These five issues are common, but they’re avoidable with the right systems and support. At CFO to Grow, we help St. Louis businesses clean up their books, improve cash flow, and get back to focusing on growth.
📞 Call or text: 636-236-7852
📧 Email: Tran@CFOtoGrow.com
