Tax Tips
Practical tax moves organized by when the door closes on them — what has to happen before December 31, what's still open until April, and what matters year-round.
Most tip lists are organized by who you are. This one is organized by when the door closes, because that decides whether a tip is worth anything to you today. Nearly everything that lowers a tax bill has to happen inside the tax year. After December 31 you are not planning, you are reporting.
Your checklist
- Before December 31
Max the plan you already have
The 2026 elective deferral limit is $24,500, plus $8,000 at 50 and $11,250 at ages 60 to 63.
Why it matters
Deferrals come out of payroll, so “I’ll do it in April” does not exist. The last paycheck of the year is the last chance. The 401(k) and 403(b) limit is shared across every plan you have; a governmental 457(b) has its own limit.
- Employee
- Self-employed or owner
- Before December 31
Look for a second plan
W-2 plus 1099 income often means a solo 401(k) can sit alongside a workplace plan.
Why it matters
The §415(c) cap of $72,000 generally applies per plan, not per person, while your elective deferral is shared across plans. A solo 401(k) next to a hospital 403(b) is the most commonly missed opportunity I see.
- Self-employed or owner
- Before December 31
Decide on a Roth conversion while you can see the year
A conversion is a December decision made with November information.
Why it matters
By November you roughly know your income and how much room is left in your bracket. In April you are only reporting what happened. Try the bracket tool on the Tax Rates page to see where a conversion would land.
- Employee
- Self-employed or owner
- Retiree
- Before December 31
Harvest losses on purpose, not by reflex
Realized losses offset gains, then up to $3,000 of ordinary income.
Why it matters
Watch the wash sale rule: buying a substantially identical position within 30 days before or after the sale disallows the loss.
- Investor
- Before December 31
Give before the year ends, and get the receipt
A written acknowledgment is required for any gift of $250 or more.
Why it matters
Appreciated stock held over a year is usually a better gift than cash: you deduct fair market value and never realize the gain. Some people bunch two years of giving into one to clear the standard deduction.
- Employee
- Self-employed or owner
- Investor
- Retiree
- Before December 31
Buy equipment only if you need it
Section 179 and bonus depreciation work only if the asset is in service by year end.
Why it matters
Buying something you do not need to save 30 cents on the dollar is not a strategy. Buying what you were going to buy anyway, before December 31 instead of after, is.
- Self-employed or owner
- Before December 31
Check your withholding one more time
Withholding counts as paid evenly across the year, whenever it actually happened.
Why it matters
A December change to your W-4 can fix an underpayment from March. An estimated payment cannot do that.
- Employee
- Before December 31
Take required distributions by December 31
If you must take a required minimum distribution, the deadline is year end.
Why it matters
The first one can wait until April 1 of the following year, but then two land in the same tax year. Missing one carries a penalty, so it is worth setting a date now.
- Retiree
- Before December 31
Use or fund the HSA
2026 limits: $4,400 self-only, $8,750 family, plus $1,000 at 55 and over.
Why it matters
An HSA is the one account that can be deductible going in, grow untaxed and come out untaxed for medical costs. Contributions for the year can be made until the April filing deadline.
- Employee
- Self-employed or owner
- January to April
Fund an IRA for last year
Prior-year IRA and HSA contributions can be made until the April filing deadline.
Why it matters
The 2026 IRA limit is $7,500, plus $1,100 at 50 and over. Tell the custodian which year the contribution is for.
- Employee
- Self-employed or owner
- January to April
A SEP-IRA can be funded as late as the extended due date
The one meaningful retirement lever still open in September.
Why it matters
That makes it a useful backstop for a business owner who learns what the year looked like only after the books close.
- Self-employed or owner
- January to April
Gather documents once, completely
A second and third round of “can you also send…” is what slows a return down.
Why it matters
Prior-year return, every W-2, 1099 and K-1, mortgage interest, property tax, tuition statements, and anything unusual about the year. Brokerage forms are often revised into March, so wait for the corrected ones.
- Employee
- Self-employed or owner
- Investor
- Homeowner
- Retiree
- January to April
File an extension if you need one, and pay with it
An extension moves the filing deadline, never the payment deadline.
Why it matters
The failure-to-file penalty is roughly ten times the failure-to-pay penalty, so extending is almost always right. Just send an estimate of what you owe along with it.
- Employee
- Self-employed or owner
- Investor
- Any time
Separate business and personal money completely
One dedicated account and one dedicated card.
Why it matters
This does more for the defensibility of your deductions than any other habit, and it cuts bookkeeping time in half.
- Self-employed or owner
- Any time
Keep records at the time, not after
Mileage logs and home office documentation written at the time hold up.
Why it matters
The same information reconstructed from memory in March is the most common weak point in a small business examination.
- Self-employed or owner
- Homeowner
- Any time
Revisit your entity as the business changes
The right structure at formation is often wrong three years later.
Why it matters
The S-corp election has a hard March 15 deadline for the current year. Deciding in November that you wish you had elected is a worse position than deciding in February.
- Self-employed or owner
- Any time
Update your W-4 after anything changes
Marriage, divorce, a second job, a new child, a spouse returning to work.
Why it matters
The form was redesigned and no longer uses allowances, so the mental model most people have for it is out of date.
- Employee
- Any time
Treat 1099 income as a business, because it is one
Moonlighting, locums, consulting, expert work: all carry self-employment tax and estimates.
Why it matters
Folding it into a normal return is where people both overpay and get surprised. The planner on the due dates page shows the quarterly numbers.
- Self-employed or owner
- Any time
Open the mail from the IRS
The response deadline runs from the date printed on the notice.
Why it matters
Most notices are automated matching that resolves in writing. Ignoring one is how a small correction becomes a collection issue.
- Employee
- Self-employed or owner
- Investor
- Homeowner
- Retiree
- Any time
Know the annual gift exclusion
You can give up to $19,000 per person in 2026 without a gift tax return.
Why it matters
Gifts above that are not automatically taxed, but they generally need a return filed. Payments made directly to a school or a medical provider are not counted as gifts.
- Retiree
Nothing matches that combination. Try “All” above.
Read out of Notice 2025-67 in September 2026. Current for tax years 2025 and 2026. If you are relying on one, confirm it at the source.
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