Many seniors (and their families responsible for filing tax returns for them) have gotten into the habit of just claiming the standard deduction instead of itemizing. That’s because seniors typically pay little or no mortgage interest, and they usually don’t owe much for state and local income and property taxes either. So the most common itemized deductions often amount to little or nothing.

Plus, folks age 65 and older get larger standard deductions. All that said, claiming the standard deduction may not be the right answer if an older taxpayer has significant medical expenses.

As you may know, medical expenses can only currently be deducted by seniors to the extent they exceed 7.5% percent of adjusted gross income (AGI) for 2017 and 2018 (down from 10% thanks to the passage of the Tax Cuts and Jobs Act of 2017). In adding up expenses, don’t make the common mistake of forgetting to count Medicare insurance premiums. Together with other out-of-pocket costs, Medicare premiums can easily put you over the percent-of-AGI threshold and also cause an older taxpayer’s total itemized deductions to exceed the standard deduction amount.

Here’s how to find out if a tax bill can be reduced by itemizing.

Identify Outlays that Count as Medical Expenses

To figure out if you have enough medical expenses to benefit from itemizing, add up the following.

1. Premiums for Medicare Parts B, C, and D Coverage. Seniors enrolled in Medicare can count premiums for Medicare Part B coverage (for medical costs other than hospital bills), Part C coverage (for Medicare Advantage policies), and Part D coverage (for prescription drugs) as medical expenses:

• For most people, the 2018 the Part B premium is $134.00 per month (or about $1,608 per year) and could be as high as $428.60 per month ($5,143 per year). If both you and your spouse are covered, these amounts could double.
• Part C premiums depend on the plan, but they can be several thousand per year for each covered person.

Higher-income individuals pay a monthly Medicare Part D surcharge in addition to the plan amount. For 2018, these surcharges range from $13.00 per month to $74.80 per month for each covered person (up from $12.70 to $72.90 in 2017).

These Medicare coverage premiums are generally withheld from Social Security benefit payments. If so, you can find the premium amounts for each year on Form SSA-1099 (Social Security Benefit Statement), which beneficiaries should receive shortly after the end of each year.

2. Premiums for Supplemental Medicare Coverage (Medigap Insurance). Seniors can also count premiums paid for private Medicare supplemental insurance policies (often called Medigap coverage) as medical expenses. The cost depends on the plan, but annual premiums can easily amount to $1,000 to $2,000 per covered person or more.
3. Premiums for Qualified Long-Term Care Coverage. Premiums for qualified long-term care insurance also count as medical expenses, subject to age-based limits. For each covered person, count the lesser of: the actual premiums paid for the year or the age-based limit from below.

4. Out-of-Pocket Medical Expenses. Many seniors also incur significant out-of-pocket outlays due to insurance co-payments and deductibles and for dental and vision care. Be sure to add these into the mix.
5. Medical Expenses Paid for Relatives. Did you pay health premiums or uninsured medical expenses for a qualifying relative this year? If you did, count these outlays too. For a person to be your qualifying relative, you generally must pay over half of his or her support for the year, and the person must be your adult child, son-in-law, daughter-in-law, grandchild, father, stepfather, father-in-law, mother, stepmother, mother-in-law, brother, stepbrother, brother-in-law, sister, stepsister, sister-in-law, aunt, uncle, niece, or nephew. It doesn’t matter if the relative lives with you or not.

Add Qualifying Medical Expenses and Subtract 10% of AGI

As mentioned earlier, most Medicare participants can claim itemized deductions in 2017 and 2018, for medical expenses to the extent the expenses exceed 7.5% of AGI. For example, say your 2017 AGI is $80,000, and you have $15,000 of medical expenses from the preceding list. Your itemized medical expense deduction is $9,000 [$15,000 minus $6,000 (7.5% of your $80,000 AGI)].

Do the Final Calculations

As you can see, you can claim a significant itemized deduction for medical expenses (even after subtracting the percent-of-AGI threshold), the next step is to identify any other potential itemized deductions for the year. These can include (among other things):

• State and local income and property taxes (including taxes on cars, boats, and other personal property).
• Home mortgage interest (if any).
• Charitable contributions.

Add these to your medical expense deduction, and see if the total exceeds your standard deduction amount of:

• For 2018, $12,000 if you are unmarried, but $13,600 if you are unmarried and 65 years or older as of December 31, 2017 ($7,900 in 2017).
• For 2018, $24,000 if you file jointly, but $26,600 if both you and your spouse are 65 or older as of December 31, 2018 (in 2017, $15,200). The 2018 amount is $25,300 if only one spouse is 65 or older as of year end ($13,950 in  2017).
• For 2018, $18,000 if you use head-of-household filing status, or $19,300 if you were 65 or older as of December 31, 2017 (up from $10,900 in 2017).

Obviously, if your total itemized deductions exceed the applicable standard deduction amount, you should forgo the standard deduction and instead claim itemized deductions, on Schedule A of Form 1040, when you file your return.

Note: If a senior taxpayer is self-employed and qualifies for the self-employed health insurance deduction (available for itemizers and non-itemizers), you may be able to add Medicare health insurance premiums to your self-employed health insurance deduction. Contact your tax adviser if this issue affects you.

You May Be Eligible for a Refund

If you do the calculations explained in this article, you may discover that itemizing is the way to go. If you failed to itemize for earlier years, you can usually recoup the tax savings for up to three earlier years by filing amended returns and receiving a refund. However, it’s much easier to simply get it right the first time. Contact your tax advisor if you’re interested in filing amended returns or want additional information.