How to Prepare for Tax Season: Common Mistakes and How to Avoid Them

By Mark Hannon

With tax season upon us, it’s time to take stock of your financial records and note any changes that may impact your filing this year. Our NPTC Tax team is here to help.

Tax season is the annual period when individuals and businesses prepare, file, and submit their income tax returns for the previous year. While it may feel like a once-a-year administrative task, tax season plays a critical role in your broader financial picture. The way you prepare, the information you gather, and the decisions you make during this time can directly affect your tax liability, cash flow, and long-term financial outcomes.

Approaching tax season proactively allows you to stay organised, identify potential issues early, and make informed decisions rather than rushed ones. With the right preparation, tax season becomes less about reacting to deadlines and more about ensuring your financial records accurately reflect your situation and support your broader goals.

When does tax season begin and what deadlines should you know?

Tax season typically begins in late January, when the Internal Revenue Service begins accepting and processing federal tax returns. While the exact start date may vary slightly each year, most taxpayers can expect tax season to open once employers and financial institutions have issued W-2s, 1099s, and other required tax documents.>/p>

While April may feel far away at the start of tax season, there are several important deadlines to keep in mind throughout the filing period, including:

• Late January: Tax season officially begins and tax returns can be filed. In 2026 tax season begins on the 26th of Jan.

• Mid-April: Standard deadline for filing individual federal tax returns and paying any taxes owed. In 2026 this date is the 15th of April.

It is important to note that filing an extension allows additional time to submit your return but does not extend the deadline for paying taxes owed. Interest and penalties may still apply if payments are made after the original due date.

How to prepare for tax season: a step-by-step checklist

Preparing for tax season is far easier and more effective when approached as a structured process rather than a last-minute task. Taking the time to review your financial activity, organise documentation, and identify any changes early can help reduce errors and ensure you are fully prepared when it is time to file.

Below is a step-by-step checklist to help you approach tax season with confidence and clarity.

Gather all income documents

Begin by collecting all records related to your income for the year. This typically includes employment income, independent or contract work, and investment activity. Common documents may include W-2s, 1099 forms, and investment or brokerage statements. Ensuring these records are complete and accurate at the outset helps prevent delays or corrections later in the filing process.

Organise deduction and credit records

Next, gather documentation that supports any deductions or credits you may be eligible to claim. This may include receipts, contribution records, or statements related to education expenses, charitable giving, childcare, or medical costs. Keeping these records organised, either digitally or physically, allows you to easily substantiate claims and avoid overlooking potential tax benefits.

Review last year’s tax return

Looking back at your previous tax return can be a valuable preparation step. Review it for any recurring items, carryovers, or changes that may still apply this year. This can help identify deductions, credits, or reporting requirements that are easy to miss if you start from scratch each year.

Confirm personal and filing information

Before filing, verify that your personal information is up to date and accurate. This includes your name, address, Social Security number, and filing status. Even small discrepancies can delay processing or create complications, so confirming these details early helps ensure a smoother tax season.

Flag complex financial events

Certain financial or life events can significantly affect your tax situation and may require additional planning or documentation. These can include the sale of assets, receipt of an inheritance, changes in business ownership or income, or major investment activity. Identifying these events in advance allows time to understand their tax implications and gather the necessary records.

Consider common life changes that affect your taxes

Life changes often have tax consequences, even if they occur partway through the year. Marriage, divorce, the birth of a child, relocation, or changes in employment status can all impact how you file and what benefits may be available. Accounting for these changes early ensures your tax return accurately reflects your current circumstances.

Decide whether professional support is needed

Finally, assess whether your situation would benefit from professional tax guidance. Individuals with multiple income streams, investments, or complex financial events often find that working with a tax professional helps improve accuracy, reduce risk, and identify planning opportunities that may otherwise be missed.

Common mistakes made during tax Season

We’re well-versed in the common mistakes people make during tax season that can complicate the filing process and comprise their tax benefits. Considering these trends, we’ve synthesized best practices to help filers avoid filing pitfalls and effectively navigate tax season.

Here are some red flags you should avoid when filing your taxes:

• Procrastinating Filing Taxes or Ignoring Tax Deadlines. Tax season can often creep up on us. That’s why it’s important to research tax deadlines and proactively prepare your records. Many make the mistake of waiting until the last minute to start their tax returns, leaving them susceptible to missing the filing or payment deadline and incurring penalties. To avoid this mistake, set a calendar reminder with key deadlines and get started early on gathering your necessary documents.

• Failing to Organize Financial Records. As financial records flood in, it’s easy to misplace W-2s, 1099s, receipts, or deduction records. We recommend using a digital or physical filing system to organize all your tax-related documents.

• Overlooking Eligible Deductions and Credits. The IRS offers a host of deductions that may apply to you, including student loan interest, home office expenses, or childcare credits. Review IRS guidelines or consult a tax professional to ensure you claim all applicable deductions and credits.

• Not Updating Personal Information. Changes in life circumstances, including marriage, divorce, or relocation, will likely impact your filing status. Make sure to notify the IRS and relevant financial institutions of any changes you have experienced over the past year.

• Using the Wrong Filing Status. The filing status you select will directly affect your tax benefits. It’s important to research the criteria for each status and select the one that accurately reflects your situation.

• Neglecting Estimated Tax Payments. Tax filings are an ongoing process. Many forget to pay quarterly taxes if they’re self-employed or have multiple income sources. To avoid penalties, make sure to calculate and pay your estimated taxes throughout the year.

• Overlooking Tax Law Changes and Failing to Seek Professional Help When Needed. Let’s face it, tax season can be… taxing. Attempting to handle complex tax situations without adequate knowledge of the tax laws can hinder your return. Remember, there are many professionals available to walk you through the process. Consider hiring a tax professional for guidance and accuracy.

• Not Keeping a Copy of Your Return. After you file your taxes, keep your return and supporting documents for future reference. We recommend keeping digital and/or physical copies for at least three years.

By following these guidelines, you can navigate tax season with greater ease and ensure you’re maximizing your benefit this year. Your Nixon Peabody team is here to support and guide you every step of the way. Whether you’re revisiting your goals, navigating complex life changes, or staying ahead of market trends, we’re committed to helping you make informed decisions and reach your financial aspirations. Let’s work together to make this year a milestone in your financial journey.

FAQs

When does the 2026 tax season start?

Tax season typically begins in late January, when the Internal Revenue Service begins accepting federal tax returns. For 2026, tax season officially starts on 26 January, marking the first day returns can be filed and processed.

How early should I start preparing for tax season?

It is best to begin preparing for tax season as soon as you start receiving income and tax documents, which often arrive in January. Starting early gives you time to organise records, identify potential issues, and avoid last-minute pressure as filing deadlines approach.

What documents do I need to prepare for tax season?

Common documents include income statements such as W-2s and 1099s, investment statements, records of deductible expenses, and documentation related to credits you may be eligible for. Reviewing the prior year’s tax return can also help identify recurring or carryover items.

What happens if I miss the tax filing deadline?

Missing the filing or payment deadline may result in interest or penalties. While you can request an extension to file, any taxes owed are still generally due by the original deadline. Starting preparation early can help reduce the risk of missed deadlines.

Should I work with a tax professional during tax season?

If your financial situation involves multiple income streams, investments, business activity, or major life changes, working with a tax professional can help improve accuracy and reduce risk. Professional guidance can also help identify planning opportunities that may not be immediately obvious.

Mark Hannon
Director of Tax Services
+1 617.345.1064
mhannon@nixonpeabody.com