A Complete Guide from the IRS

Figuring out whether to itemize your deductions or take the standard deduction can feel like solving a puzzle. This guide breaks down everything you need to know about Schedule A (Form 1040) for the 2015 tax year, using information directly from IRS.gov.

What the Form Is For

Schedule A (Form 1040) is the IRS form you use to claim itemized deductions on your 2015 federal income tax return. Think of it as an alternative to the standard deduction—a way to reduce your taxable income by listing specific expenses you paid throughout the year.

2015 Standard Deduction Amounts

• Single filers: $6,300
• Married filing jointly: $12,600
• Head of household: $9,250
• Married filing separately: $6,300

You should only use Schedule A if your total itemized deductions exceed your standard deduction. The form allows you to deduct expenses in seven major categories:

• Medical and dental expenses
• State and local taxes
• Home mortgage interest
• Gifts to charity
• Casualty and theft losses
• Job expenses
• Certain miscellaneous deductions

The completed Schedule A attaches to your Form 1040, and the total from line 29 (or line 30 if your income exceeds $154,950) carries over to Form 1040, line 40.

When You'd Use It (Late or Amended Returns)

Original Filing

If you filed your 2015 return on time, you would have submitted it by April 18, 2016 (the deadline was pushed from April 15 due to Emancipation Day in Washington, D.C.).

Late Filing

If you missed the deadline and never filed your 2015 return, you can still file it now, though you may face late-filing penalties if you owed taxes.
There's no time limit for filing a late return, but you'll want to file as soon as possible to claim any refund you’re entitled to—though the refund window has likely closed.

Amended Returns

According to IRS rules, you generally have three years from the date you filed your original 2015 return (or two years from when you paid the tax, whichever is later) to file an amended return on Form 1040-X to claim a refund.
For most taxpayers who filed on time in 2016, the deadline to amend the 2015 return for a refund was April 2019.
However, you can still file an amended return to correct errors, even if you can't claim a refund.

Why You Might Amend

You’d file Form 1040-X if you:

• Originally took the standard deduction but later realized your itemized deductions were higher
• Discovered eligible expenses you forgot to include on your original Schedule A

Key Rules for 2015

Medical and Dental Expenses

You can only deduct medical and dental expenses that exceed a threshold based on your age:

• 7.5% of AGI if you or your spouse were born before January 2, 1951 (age 65 or older)
• 10% of AGI if both of you were younger

Example: If your AGI was $50,000 and you qualify for the 7.5% threshold, you'd need more than $3,750 in medical expenses to deduct anything.

Taxes You Paid

You must choose between deducting state and local income taxes or state and local general sales taxes—you cannot deduct both.
Most people choose income taxes unless they live in a state with no income tax or made major purchases where sales tax was significant.

Home Mortgage Interest

Your deduction may be limited if you took out mortgages after October 13, 1987.
The limit applies to:

• Mortgages totaling over $1 million ($500,000 if married filing separately) used to buy, build, or improve your home
• Mortgages totaling over $100,000 ($50,000 if married filing separately) used for other purposes, like home equity loans

Charitable Contributions

• Cash gifts of $250 or more require written acknowledgment from the charity.
• Non-cash gifts over $500 require Form 8283.
• You can’t deduct the value of benefits received in exchange for a donation.

Itemized Deduction Limitation

If your AGI exceeded $154,950 in 2015, your total itemized deductions may be reduced.
Complete the Itemized Deductions Worksheet in the instructions to calculate this limitation.

Miscellaneous Deductions

Unreimbursed employee expenses, tax preparation fees, and investment expenses are deductible only to the extent they exceed 2% of your AGI.

Step-by-Step: How to Complete Schedule A (High Level)

Step 1: Gather Your Documentation

Collect:

• Forms W-2 (for state taxes withheld)
• Form 1098 (mortgage interest)
• Receipts for medical expenses and charitable contributions
• Documentation for other deductible expenses

Step 2: Calculate Medical and Dental Expenses (Lines 1–4)

Total all qualifying medical expenses, enter your AGI from Form 1040 line 38, multiply by 7.5% or 10% depending on age, and subtract to find your deductible amount.

Step 3: Report Taxes You Paid (Lines 5–9)

Choose between state/local income taxes or general sales taxes.
Add real estate taxes and personal property taxes, then total these amounts.

Step 4: Report Interest Expenses (Lines 10–15)

Enter mortgage interest from Form 1098, additional mortgage interest not reported, points, mortgage insurance premiums, and investment interest.

Step 5: Report Charitable Gifts (Lines 16–19)

Separate cash contributions from non-cash contributions. Include any carryover from prior years and total your charitable giving.

Step 6: Report Other Deductions (Lines 20–28)

Include casualty losses (Form 4684), unreimbursed job expenses (Form 2106), tax preparation fees, and other miscellaneous deductions exceeding 2% of AGI.

Step 7: Calculate Your Total (Line 29)

If your AGI is $154,950 or less, simply add lines 4 through 28.
If your AGI exceeds this amount, use the Itemized Deductions Worksheet to calculate your limited deduction.

Step 8: Transfer to Form 1040

Enter your total itemized deductions on Form 1040, line 40.

Common Mistakes and How to Avoid Them

Mistake #1: Not Keeping Adequate Records

Always keep receipts, canceled checks, bank statements, and acknowledgment letters from charities.
For medical expenses over $75, keep itemized bills showing who was treated and the nature of the expense.

Mistake #2: Including Reimbursed Expenses

Don’t deduct medical expenses reimbursed by insurance or paid through an FSA or HSA.

Mistake #3: Choosing the Wrong Tax Deduction

You cannot deduct both state income taxes and sales taxes. Calculate both and pick the one with the bigger deduction.

Mistake #4: Missing the Percentage Thresholds

Medical and miscellaneous deductions have AGI-based thresholds. Only the portion above the limit is deductible.

Mistake #5: Forgetting State Tax Refunds

If you received a state tax refund for a prior year where you itemized, report it as income on Form 1040, line 21.

Mistake #6: Claiming Non-Deductible Items

Common non-deductible items include:

• Federal income taxes
• Social Security taxes
• Life insurance premiums
• Cosmetic surgery (unless medically necessary)
• Over-the-counter medications

Mistake #7: Exceeding Mortgage Interest Limits

If you refinanced or took out a home equity loan, review IRS Publication 936 to ensure you’re within allowable limits.

What Happens After You File

Acceptance and Processing

The IRS checks your return for errors and inconsistencies.

• E-filed returns: acknowledgment within 24–48 hours
• Paper returns: processed within 6–8 weeks

Refund or Payment

• Refunds typically arrive within 21 days for e-filed returns.
• Payments must be postmarked by the filing deadline to avoid penalties and interest.

Potential Audit

Returns with unusually high deductions may be reviewed. Keep thorough documentation as your best defense.

Record Retention

Keep your 2015 tax return, Schedule A, and supporting records for at least three years (preferably six or seven for certain deductions).

State Returns

If you itemized federally, your state return may also need to be itemized depending on state rules.

Frequently Asked Questions

Q1: Should I itemize or take the standard deduction?

Calculate both! If your itemized deductions exceed your standard deduction ($6,300 single, $12,600 married filing jointly in 2015), itemize.

Q2: Can I deduct medical expenses I paid for my parents?

Yes, if you provided more than half of their support, even if they aren’t dependents on your return.

Q3: What if I lived in multiple states in 2015?

You can deduct taxes paid to all states where you lived or earned income.
For sales tax, prorate based on days lived in each state.

Q4: Are points I paid when buying my home fully deductible?

Yes, if they meet IRS requirements and were paid on your main home purchase.
Points from refinancing are typically deducted over the loan’s life.

Q5: Can I deduct my property taxes if they’re included in my mortgage payment?

Yes, but only the portion your lender actually paid to the taxing authority in 2015.

Q6: What’s the difference between line 10 and line 11 for mortgage interest?

• Line 10: Interest reported on Form 1098
• Line 11: Interest not reported (e.g., seller-financed homes)

Q7: If my itemized deductions are close to the standard deduction, should I still itemize?

Generally no—unless you can use a “bunching” strategy to exceed the threshold one year, then take the standard deduction the next.

Important Resources

All information in this guide comes from official IRS sources:

• 2015 Schedule A Form (PDF)
• 2015 Schedule A Instructions (PDF)
• IRS Schedule A Information Page
• IRS Amended Returns Information

Disclaimer: This guide is for informational purposes only and does not constitute tax advice.
Tax laws are complex and individual situations vary. Always consult a qualified tax professional for advice specific to your circumstances.