As another common question small business owners raise at the start, quarterly estimated taxes cause a bit of implicit worry. People have heard the word “penalty,” and they are not sure how much to save or when the money is actually due. The good news is that the system is simpler than it looks. Once you set it up, it mostly runs itself. Here is the whole thing, start to finish.

Do I even have to do this?

Here is the simple test. If you expect to owe at least $1,000 in federal tax for the year after any withholding, you are supposed to pay as you go. That covers most sole proprietors, freelancers, gig workers, partners, and S-corp owners who take profit beyond their paycheck. By law, the federal income tax is pay-as-you-go. You are expected to pay tax as you earn income during the year, not in one lump sum at filing. IRC §6654 backs this up with a penalty if you underpay along the way.

If you also hold a W-2 job, you have a shortcut. You can raise the withholding on that paycheck to cover the tax on your side income. Withholding counts as paid evenly across the year, even if it all lands in December. That one move spares many people the quarterly routine entirely.

How much should I set aside?

Start with a working rule: save 25 to 30 percent of every dollar of profit, not revenue. Profit is what is left after business expenses. Move that money into a separate savings account the day it comes in, and treat it as money you no longer own. For most owners in the lower and middle brackets, 25 to 30 percent covers both income tax and self-employment tax with a little cushion. If you are in a higher bracket or a high-tax state, lean toward 35 percent.

Why so high? Because self-employment tax stacks on top of income tax. Self-employment tax is 15.3 percent of your net earnings: 12.4 percent for Social Security and 2.9 percent for Medicare. For 2026, the Social Security portion applies to the first $184,500 of net earnings. The Medicare portion has no cap. When you had an employer, they paid half of this for you. On your own, you pay both halves.¹ You do get to deduct half of your self-employment tax on your Form 1040, which softens the blow a little, but the cash still has to go out the door.

The safe harbor: how to avoid a penalty

You do not have to predict your tax to the dollar. The IRS gives you a safe harbor. Pay one of these amounts in even installments and the underpayment penalty disappears, even if you still owe more at filing time.

Option one: pay 90 percent of what you will actually owe this year. Option two: pay 100 percent of what you owed last year. If your prior-year adjusted gross income was over $150,000, that second number rises to 110 percent. The prior-year option is the safer bet because last year’s number is already known. Take the total tax from last year’s return, multiply by 100 or 110 percent, and divide by four. That is your quarterly target.

One caveat if your income is uneven. The safe harbor assumes four roughly equal payments. So if most of your money arrives late in the year and you pay it all in the final quarter, you can still owe a small penalty for the earlier ones. There is a way to line your payments up with when you actually earned the income, but it adds paperwork, so ask your CPA if your income swings a lot.

When do I send it in?

Estimated taxes are due four times a year. The periods are not even three-month blocks, which surprises people, but the dates are what matter. For the 2026 tax year, the deadlines are:

• First payment: April 15, 2026

• Second payment: June 15, 2026

• Third payment: September 15, 2026

• Fourth payment: January 15, 2027

If a date falls on a weekend or holiday, it shifts to the next business day. Put all four in your calendar now, with a reminder a few days early. A payment counts as on time based on the date you submit it electronically, or the postmark if you mail it.

How do I actually pay?

The easiest free method is IRS Direct Pay on IRS.gov. It pulls straight from your bank account, costs nothing, and gives you a confirmation number. Save that number. For business taxes and larger operations, the Electronic Federal Tax Payment System (EFTPS) is the standard, though it takes about a week to enroll the first time, so do not wait until a deadline. You can also pay by card for a processing fee, or mail a check with a Form 1040-ES voucher. Whatever you choose, keep a record of each payment so you can report the total correctly at filing.

Do not forget your state. Most states with an income tax run their own estimated payment system, with its own deadlines and vouchers. The federal payment does not cover it. Set aside for both.

A few habits that make this painless

Three habits keep estimated taxes from becoming a crisis. First, sweep your set-aside percentage into a separate account every time you get paid, not at quarter-end. Second, use the prior-year safe harbor so you always know your target number. Third, do a quick mid-year check with your CPA, especially if your income jumped, so the back half of the year does not surprise you. Estimated taxes are not hard once the system is in place. They are just easy to forget, and the penalty is the price of forgetting.

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Disclaimer: This essay is for educational purposes only and is not tax advice for your specific situation. Federal and state tax laws change, and your facts matter. Please consult a licensed CPA or tax attorney before acting on anything you read here.

Shang (Shawn) Zhou, CPA

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1. Some entity choices change this. Electing S-corp status, for instance, can keep profit above a reasonable salary out of self-employment tax, and income such as rental real estate is generally exempt under IRC §1402. Those exceptions are a topic for another discussion. ↩︎

One of the very first decisions you make as a business owner, often before you have earned a dollar, is what structure to operate under. It feels like a box-checking chore. It isn’t. The structure you pick decides how your profit is taxed, how much self-employment tax you hand over, and how freely you can split income with a partner. Here is how the main choices compare, and how to pick one.

1. First, the menu

You have five options worth knowing: the sole proprietorship, the general partnership, the limited liability company (LLC), the S corporation, and the C corporation.

The first two you get for free, whether you want them or not. One person selling something is automatically a sole proprietor. Two or more people doing it together, with nothing on paper, are automatically a general partnership. The LLC is a formal entity you register with your state.

Here is the part that confuses almost everyone: an S corporation isn’t really a separate kind of company – it’s a tax election. An LLC or a corporation files a form with the IRS asking to be taxed under the S-corp rules. So most small business owners are really choosing an LLC first, then choosing how it gets taxed.

2. Going it alone

Starting solo? Your default is the sole proprietorship. No filing, no separate return. Your profit lands on Schedule C of your personal Form 1040. Beautifully simple.

The simplicity comes with two strings attached. First, every dollar of net profit gets hit with self-employment tax, 15.3% (12.4% for Social Security on income up to $184,500 in 2026, plus 2.9% for Medicare), and that is before regular income tax. Second, there is no wall between you and the business. If it gets sued, your house and savings are within reach.

A single-member LLC fixes the second problem without touching the first. The IRS treats a one-owner LLC as a “disregarded entity”: for tax purposes it simply ignores it, and you file the same Schedule C as before. You get the legal wall; your tax bill doesn’t budge. For most solo owners, that makes the LLC cheap insurance and the sensible place to start.

3. Teaming up with a partner or two

The minute you go into business with one or two other people and don’t form anything, the law has chosen for you: you’re a general partnership. That’s a risky default, because each partner is personally on the hook for the whole business, including a debt a partner runs up without asking you.

The cleaner move is a multi-member LLC. By default the IRS taxes it as a partnership: the business files an information return (Form 1065) and hands each owner a Schedule K-1 showing their share of the profit, which each person reports on their own return. The business itself pays no income tax. Everything flows through to the owners, and, just like a sole proprietor, an active partner generally pays self-employment tax on their share.

Partnership taxation has one feature a solo owner never gets: flexibility. You don’t have to split profit and loss strictly by ownership percentage. Say one partner puts in the startup cash and the other does the daily work – you can steer more of the early losses to the funder and more of the profit to the one running the shop. The rules call these “special allocations,” and they must reflect real economics, not just tax wishes. Whatever you agree to, put it in a written operating agreement: who owns what, who does what, and what happens the day someone wants out.

4. The S-corp election: a tax move, not a new company

Once a business, solo or partnered, is reliably profitable, the S-corp election is worth a serious look. The appeal is specific: in an S corp, an owner who works in the business takes a “reasonable salary” as a W-2 employee, and the leftover profit comes out as a distribution that escapes the 15.3% self-employment tax. On a healthy profit, that adds up.

It isn’t free money. You have to run real payroll, file a separate return (Form 1120-S), and pay yourself a salary that is genuinely reasonable for the work; the IRS watches that number closely. As a rough gauge, the election starts paying off once profit runs comfortably past a reasonable salary, often by $40,000 or more. One catch for partners: an S corp must split profit strictly by ownership percentage, so a partnership’s special-allocation flexibility disappears.

5. The C corporation and how to choose

The C corporation is the only structure here that pays its own income tax, a flat 21%, and then taxes its owners again on any dividends they take. That “double taxation” is why most small, owner-run businesses pass on it. Where it shines is raising money: venture capital investors almost always expect a C corporation, and the structure can also let founders exclude a large share, sometimes all, of their gain when they sell stock held for several years.

So how do you choose? If you’re solo and keeping life simple, a single-member LLC taxed as a sole proprietor is the natural home – add the S-corp election later, once profit justifies it. Partnering up? A multi-member LLC taxed as a partnership gives you the legal wall plus the freedom to split income fairly. And if you plan to raise serious outside capital, look hard at the C corporation. The reassuring part: none of these doors lock behind you – the right answer for year one often isn’t the right answer for year five.

A final word

The cost of getting this decision wrong compounds quietly: overpaid self-employment tax, a missed election, a profit split that doesn’t hold up under a closer look. The right structure depends on details a general guide can’t see: your state’s rules, your income, your partners, and where you want the business to be in five years. That’s the kind of question worth a real conversation. If you’d like a tailored review of which structure fits your business, or a broader look at your tax strategy, reach out anytime HERE. Let’s put the most money where it belongs: back in your business, so that you can focus on what you do best to take your business to the next level.

Shang (Shawn) Zhou, CPA

If I had to pick the single tax question I get asked the most by small business owners, it would be some version of this: “I work from my house. Can I write off part of it?”

The short answer is yes, probably. The longer answer involves a few rules that trip people up every year, a couple of math choices that can leave real money on the table, and a recent piece of legislation that closed the door on this deduction for a big group of people. Let’s walk through all of it together right now.

Who Actually Qualifies (and Who Doesn’t, Anymore)

Before we talk about square footage and utility bills, we have to start with the threshold question: are you even allowed to take this deduction?

Under current federal tax law, the home office deduction is available to self-employed people and small business owners, sole proprietors filing Schedule C, partners in partnerships, members of LLCs, and so on. If you run your own business and your home is where you do it, you’re in the right room.

Here’s the part that surprises people: if you’re a W-2 employee who works from home, even if your employer requires you to work from home, even if they don’t give you any office space at all, you cannot deduct your home office on your federal return. The Tax Cuts and Jobs Act of 2017 suspended unreimbursed employee business expenses through 2025, and the One Big Beautiful Bill Act, signed into law on July 4, 2025, made that suspension permanent starting in 2026. So this is no longer a “wait it out” situation. If you receive a W-2, the door is closed.

The workaround for employees is simple but requires cooperation from your employer: an “accountable plan” reimbursement, where your employer reimburses you for legitimate home office costs and deducts them on the business side. That’s a conversation to have with your boss or HR, not your tax preparer.

For everyone else: the freelancers, the consultants, the side-hustlers with real revenue, the small business owners, this deduction is alive and well. Let’s get into how it works.

The Two Tests You Must Pass

The IRS doesn’t let you write off any old corner of your house. The space you’re claiming must pass two tests, and both are non-negotiable.

Test One: Regular and exclusive use. The “exclusive” part is where most people stumble. Your home office has to be used only for business. Not “mostly,” not “usually.” If your kids do homework at the same desk in the evening, or you fold laundry on the daybed in the corner, that space technically fails the test. The IRS doesn’t send agents to peek in your windows, but if you’re ever audited, this is the rule they’ll apply. The “regular” part is friendlier: you need to use the space consistently for business, not just a few times a year.

There are two narrow exceptions to the exclusive-use rule: storage of inventory or product samples (if your home is your sole place of business), and licensed daycare operations. Outside those, exclusivity is the rule.

Test Two: Principal place of business. The space must be your principal place of business, or a place where you regularly meet with clients or customers, or a separate structure (like a detached garage or a backyard shed) used in connection with your business. “Principal place of business” doesn’t necessarily mean you do all your work there. It means you do your most important work there, or you use it regularly for the administrative and management activities of your business and have no other fixed location where you do that work.

So a plumber who does jobs at clients’ houses all day but handles billing, scheduling, and ordering from a dedicated home office? That’s a principal place of business. A consultant who travels Monday through Thursday but works from a home office on Fridays and weekends? Same deal.

The Two Methods: Simple vs. Detailed

Once you’ve established that you qualify, you get to choose how to calculate the deduction. The IRS gives you two paths.

The Simplified Method

This one lives up to its name. You measure your home office, cap it at 300 square feet, and multiply by $5. That’s it. The maximum deduction under this method is $1,500 per year (300 × $5).

No tracking utility bills. No depreciation calculations. No allocating insurance premiums. Just a tape measure and basic multiplication. You claim it directly on Schedule C.

The simplified method is genuinely useful for people with small offices, simple finances, or low patience for recordkeeping. But $1,500 is a hard ceiling, and for many homeowners, especially in higher-cost areas, the actual numbers tell a much better story.

The Regular Method (Actual Expense Method)

This is the one that requires more work but usually pays better. The core idea: calculate the percentage of your home that’s used for business, then apply that percentage to your home-related expenses.

The percentage is almost always calculated by square footage. If your home is 2,000 square feet and your office is 200 square feet, your business-use percentage is 10%. (You can use a “number of rooms” method if all your rooms are roughly equal size, but square footage is more defensible and more common.)

Now you apply that 10% to your indirect expenses: the things that benefit the whole house, including the office. And there’s a separate, fuller treatment for direct expenses. This is where most of the planning happens.

Direct, Indirect, and Unrelated Expenses

This three-bucket framework is how the IRS organizes home expenses, and getting it right is the difference between a clean return and an awkward conversation with an examiner.

Indirect expenses (apply your business-use percentage). These are the costs that keep the whole home running, your office included. Using our 10% example:

• Electricity, gas, water, sewer, and trash service
• Homeowners or renters insurance
• HOA dues
• General repairs that benefit the whole home (roof patch, HVAC service)
• Home security system monitoring
• Rent, if you rent rather than own
• Mortgage interest and real estate taxes (homeowners only – and there’s a wrinkle here we’ll get to)
• Depreciation on the home itself (homeowners only)
• Internet and Wi-Fi: generally indirect, since you almost certainly use it personally too. Apply your business percentage. If you happen to have a completely separate business-only line, that’s a 100% direct expense.

Direct expenses (100% deductible). These benefit only the home office. If you paint just the office, that’s 100%. If you have an electrician add outlets to that room specifically, that’s 100%. New blinds for the office window? 100%. Direct expenses are the cleanest deductions you’ll find. Full write-off, no allocation.

Unrelated expenses (0% deductible). These benefit a part of the home that has nothing to do with your business. Lawn care, pool maintenance, repainting your kitchen, remodeling the kids’ bathroom – none of that is deductible, even partially. The IRS isn’t subsidizing your azaleas.

A small but persistent rule worth knowing: the basic local service charge for the first landline telephone into your home is considered a personal expense and is 0% deductible, regardless of how much business you do on it. A second landline used for business is 100% deductible. Cell phones get treated separately from the home office calculation entirely: you deduct the business-use portion as a regular business expense based on your actual usage.

The Mortgage Interest and Property Tax Wrinkle

If you own your home, you’ve probably been deducting mortgage interest and property taxes on Schedule A as itemized deductions. When you take a home office deduction using the regular method, those expenses get split: the business portion (your percentage) moves to Schedule C via Form 8829, and the personal portion stays on Schedule A.

If you use the simplified method instead, you don’t split anything. You take the full $5-per-square-foot deduction and you continue to deduct 100% of your mortgage interest and property taxes on Schedule A (if you itemize). The simplified method doesn’t require you to allocate those costs between business and personal use.

This is one of those quiet factors that can tilt the choice between methods, especially for homeowners with significant mortgage interest who also take the standard deduction. Run both calculations before you decide.

Depreciation: Powerful, but Watch the Back End

If you own your home and use the regular method, you can depreciate the business portion of your home over 39 years (residential real estate used for business is depreciated on the nonresidential schedule). For a homeowner with significant equity and a long time in business from the same house, this can add up to a real annual deduction.

Here’s the catch every CPA will warn you about: when you eventually sell your home, the depreciation you’ve claimed (or were allowed to claim, whether you took it or not) gets recaptured. That means the gain attributable to those depreciation deductions gets taxed at up to 25%, even if the rest of your gain would qualify for the Section 121 home sale exclusion.

This isn’t a reason to avoid the depreciation deduction. It’s just a reason to know it’s there. The simplified method sidesteps depreciation entirely (it’s deemed to be zero for those years), which is one reason some homeowners prefer it despite the lower ceiling.

The Income Limitation

Whichever method you use, your home office deduction can’t push your business into a tax loss. The deduction is limited to your gross income from the business, reduced by your other business expenses. In other words, the home office deduction cannot create or increase a loss.

What happens to the excess? With the regular method, any disallowed amount carries forward to future years, where it can be used when your business has enough income to absorb it. With the simplified method, there’s no carryforward. Disallowed amounts are simply lost.

For a brand-new business or a year with unusually low revenue, this is one of the strongest arguments for using the regular method even when the simplified math looks attractive.

You Can Switch Methods Year to Year

You’re not locked in. You can use the simplified method one year and the regular method the next. The choice is made annually on a timely-filed original return. Once you’ve filed with one method, you can’t amend to switch for that same year, but next year is a fresh decision.

A common pattern: use the regular method when you have significant actual expenses, switch to simplified in a quieter year or when life gets busy and you don’t have the records you need.

Recordkeeping: Boring, Critical

If you take this deduction, keep records like you might be asked to defend them. That means:

• A floor plan or measurement of your home office and total home square footage
• Utility bills, insurance statements, and repair invoices
• A clear log of mortgage interest and property taxes paid
• For homeowners, the cost basis of your home and the date you started using the office for business (you’ll need this for depreciation calculations)
• Photos of the office space showing exclusive business use, if you can manage it

The home office deduction has historically been one of the more audit-flagged items on small business returns, mostly because so many people have taken it improperly over the years. Clean records turn it from a risk into a routine line item.

A Final Word

The home office deduction is one of the genuinely good deals in the tax code for people who run their businesses from home. It rewards a structural reality of how a lot of modern work happens, and for self-employed people, it survived the OBBBA intact.

The decision tree isn’t complicated once you know the rules: confirm you qualify, run both calculation methods, pick the one that yields the bigger deduction (without ignoring the depreciation-recapture trade-off down the road), keep your records, and revisit the choice every year.

If you’re on the fence, do the math both ways before you file. The right method, the right square footage measurement, the right treatment of mortgage interest and depreciation, the right call on whether to claim it at all given your future plans for the house. These decisions add up to real money, year after year. A general guide can point you in the right direction, but it can’t run the numbers on your return. That’s what I do for small business owners like you, so that you can focus on what you do best to take your business to the next level. If you’d like a tailored review of your home office deduction, or a broader conversation about your small business tax strategy, reach out anytime HERE. Let’s find the approach that puts the most money back in your business. 

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This essay is for educational purposes and reflects U.S. federal tax law as of the 2025 tax year (returns filed in 2026), including changes made by the One Big Beautiful Bill Act. State tax treatment of home office expenses varies and is not addressed here. Always consult a qualified tax professional regarding your specific situation.