1040 Tax Filing Services
Filing a Form 1040 isn’t just about reporting income. It reflects investment activity, compensation decisions, family changes, and long-term financial choices. When those details aren’t handled correctly, the consequences can follow you for years.
Sundack CPA provides CPA-led 1040 tax filing for individuals and families with more complex tax situations. We work with clients throughout Long Island and New York City, as well as individuals with multi-state income, to ensure returns are accurate, compliant, and prepared with planning in mind — not rushed through software or volume-driven workflows.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
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What 1040 Tax Filing Covers
Form 1040 is the core individual tax return used to report income, deductions, credits, and tax obligations. For many filers, it includes multiple schedules and supporting statements that must be reported correctly to avoid errors, penalties, or audit exposure.
A properly prepared 1040 accounts for how income is earned, how assets are held, and how decisions made during the year affect both current and future tax outcomes.
Common 1040 Schedules We Prepare
- Schedule A — Itemized deductions, including mortgage interest, charitable contributions, and eligible expenses
- Schedule B — Interest and dividend income
- Schedule C — Self-employment and independent contractor income
- Schedule D — Capital gains and losses from investments
- Schedule E — Rental income and pass-through income from partnerships or S-corps
Each schedule carries its own reporting rules, documentation requirements, and planning considerations.
Who This 1040 Tax Filing Process Is For
This service is designed for:
- Individuals and families filing Form 1040
- High-income W-2 earners with equity compensation or complex deductions
- Individuals with investment income, brokerage accounts, or capital gains
- Clients with K-1 income, rental properties, or pass-through interests
- Individuals receiving RSUs, ISOs, or other stock compensation
- Clients with income earned in multiple states
- NYC residents or non-residents with New York source income
- Individuals who want clarity, legitimate tax savings, and year-round guidance, not just a once-a-year filing
If your return involves more than basic wage income, accuracy and planning matter.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
Our 1040 Tax Filing Process
- Intake & Information Gathering
We begin with a structured intake process that includes:
- Prior-year tax returns
- Current-year tax documents (W-2s, 1099s, K-1s, brokerage statements)
- Information about life and financial changes such as marriage, divorce, children, home purchases or sales, and employment changes
We review this information with purpose, looking for changes, risks, and planning opportunities.
2. Technical Review & Preparation
Your return is prepared by experienced professionals who understand individual tax complexity. We focus on:
- Accurate reporting of all income sources
- Proper treatment of investments and equity compensation
- State and local tax considerations
- Identifying missed deductions, credits, or elections
Returns are prepared with a planning mindset — not data entry.
3. Internal Review & Quality Control
Before finalizing any return, we conduct an internal review to ensure:
- Accuracy and consistency
- Compliance with current tax law
- Alignment with prior-year filings
- Identification of planning items to revisit
Quality control matters because mistakes are costly.
4. Client Review & Clear Communication
We do not send returns without explanation. Clients receive:
- A clear summary of results
- Plain-English answers to questions
- Explanation of available options and trade-offs
- Guidance on next steps, payments, extensions, or planning items
5. Filing, Follow-Through & Support
Once approved:
- Returns are filed securely and on time
- Payment instructions are provided when applicable
- We remain available for IRS or state notices and follow-up questions
We stand behind our work beyond filing day.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
Our Approach at Sundack CPA
Our Philosophy
At Sundack CPA, we believe individual tax filing should be proactive, personalized, and strategic. A 1040 tells a story about income, investments, family decisions, and future plans. Our role is to understand that full picture, report it correctly, and help clients make informed decisions year after year.
We do not treat tax filing as a compliance-only task.
Planning Is Built Into Preparation
Unlike firms that review planning options after a return is finished, we evaluate planning during the preparation process. Depending on your situation, this may include:
- Reviewing retirement contribution opportunities
- Evaluating the timing of income and deductions
- Applying capital gain and loss strategies where appropriate
- Considering charitable giving approaches
- Addressing SALT limitations and New York–specific planning
- Clearly explaining available options and the trade-offs involved
If opportunities exist, we communicate them before filing so decisions are made intentionally — not after the fact.
Why Work With a CPA for 1040 Tax Filing
DIY tax software and high-volume tax shops are built for speed, not judgment. They often miss planning opportunities, misclassify income, or overlook state and local compliance issues — especially for New York filers.
Working with a CPA means:
- Accurate treatment of complex income sources
- Proper documentation and defensible reporting
- Reduced audit and notice risk
- Correct handling of New York State and SALT considerations
- Consistency year over year
- Filing decisions made with long-term impact in mind
A 1040 filed incorrectly can cost far more than it saves.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
1040 Tax Filing for Long Island and New York City
Clients in Long Island and New York City face stricter compliance standards and more complex state and local tax considerations. We work with individuals throughout Nassau County, Suffolk County, and the five boroughs, helping navigate New York State requirements, SALT limitations, and resident versus non-resident filing issues.
If you earn income connected to New York — even while living or working elsewhere — accurate reporting is essential.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
Reliable Accounting, Stable Strategy,
Excellent
Advice
With exceptional bookkeeping, accurate tax preparation, and smart forecasting, we map out a path towards your individual or business targets and lifelong goals
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
Multi-State 1040 Filing Considerations
Individuals earning income in more than one state must report and allocate income correctly. We assist with:
- Reporting income earned across multiple states
- Applying credits for taxes paid to other states
- Proper allocation to avoid double taxation
- Preventing mismatches that trigger notices or penalties
Multi-state filing errors are common — and avoidable.
Common 1040 Filing Problems We Help Resolve
- Prior-year filing errors
- Missed deductions or credits
- Incorrect capital gains reporting
- Rental income misclassification
- K-1 reporting issues
- IRS or New York State notices
- Multi-state filing mistakes
We correct issues and put systems in place to prevent them from recurring.
At Sundack CPA, your success is our priority. We’re not just expert CPA's —we’re your financial partners, committed to helping you grow and thrive.
Ready to see the Sundack CPA difference? Connect With Us Now!
Questions? Let's Connect
Sundack CPA 1040 Tax Filing Service FAQ's
The following FAQs cover common questions about CPA-led 1040 tax filing and how Sundack CPA supports individuals with complex tax situations.
Form 1040 is the primary federal income tax return used by individuals and families to report income, deductions, credits, and tax liability. Most U.S. taxpayers are required to file a 1040, including those with W-2 income, self-employment income, investments, rental properties, or other taxable activity.
A CPA is recommended when a 1040 includes more than basic wage income. This includes investment activity, capital gains, rental properties, K-1 income, stock compensation, multi-state income, or situations where tax planning decisions affect current and future years.
Many 1040 returns include additional schedules, such as Schedule A for itemized deductions, Schedule B for interest and dividends, Schedule C for self-employment income, Schedule D for capital gains and losses, and Schedule E for rental or pass-through income. Each schedule has specific reporting rules and documentation requirements.
Tax planning is evaluated during preparation, not after filing. This can include reviewing retirement contribution options, timing income or deductions, capital gain and loss strategies, charitable giving considerations, and state and local tax impacts. When options exist, trade-offs are explained before the return is filed.
Yes. We handle 1040 returns that include brokerage activity, capital gains and losses, dividends, RSUs, ISOs, and other forms of equity compensation. Proper reporting is critical to avoid errors, underpayment, or future notices.
New York filers often face additional complexity due to state and local requirements, SALT limitations, and resident versus non-resident rules. NYC residents and individuals with New York source income must ensure income is reported and allocated correctly at the federal, state, and local levels.
Multi-state 1040 filing requires proper reporting of income earned in each state and applying credits for taxes paid to other states. Errors in allocation or reporting can result in double taxation or notices from state tax agencies.
Yes. Prior-year returns are reviewed to ensure consistency, identify errors, and uncover missed deductions or planning opportunities. This review helps prevent recurring issues and supports accurate year-over-year reporting.
If a notice is received, we assist with reviewing the issue, responding to the agency, and correcting any underlying problems. Proper documentation and accurate preparation reduce the likelihood of notices, but support is available if issues arise.
While filing occurs annually, many clients benefit from year-round guidance related to income changes, investments, retirement planning, and upcoming tax decisions. Ongoing planning helps reduce surprises and improves long-term outcomes.
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