How to Pay Maryland State Income Tax

Where and how to pay Maryland income tax

Maryland accepts state income tax payments through three main channels: online through the Comptroller's website, by mail, or through your employer's payroll system if taxes are withheld. The online method is the fastest and most common — you can pay from a checking or savings account using the Comptroller of Maryland's payment portal, and the money moves within one to two business days. If you prefer mail, you send a check with a payment voucher to the address listed on your tax notice. If you owe taxes through self-employment or have additional tax liability beyond what your employer withholds, you can also make quarterly estimated tax payments online or by mail.

The payment deadline for Maryland state income tax is the same as the federal deadline: April 15 of the following year for the previous tax year. If April 15 falls on a weekend or holiday, the deadline moves to the next business day. You can request an extension to file your return, which gives you until October 15, but an extension to file is not an extension to pay — taxes owed are still due by April 15, and interest and penalties accrue on unpaid amounts after that date.

Key Takeaways

• Maryland income tax payments go through the Comptroller's website, by mail with a payment voucher, or through employer withholding — online is fastest and most direct.
• The payment deadline is April 15 each year, the same as federal taxes, and late payments trigger interest and penalties even if you file an extension.
• If you are self-employed or have income not subject to withholding, you must make quarterly estimated tax payments on June 15, September 15, December 15, and April 15.
• You can check your payment status and account balance through the Comptroller's online portal using your Social Security number or tax ID.

Paying online through the Maryland Comptroller

The Maryland Comptroller's website hosts a payment portal where you can pay income tax, property tax, and other state taxes in one place. To pay online, you need your Social Security number or federal employer ID number, the tax year you are paying for, and access to a checking or savings account. The portal accepts payments from U.S. bank accounts only — you cannot use a credit card or debit card directly, though some banks allow you to initiate ACH transfers through their own bill-pay systems.

When you log in and enter your payment amount, the system shows you the exact date the money will arrive at the state's account. Payments made before 11:59 p.m. on a business day typically post the next business day. If you pay on a Friday, the money arrives Monday (unless Monday is a holiday). There is no fee charged by the state for online payments, though your bank may charge a fee if you use their bill-pay service instead of the Comptroller's portal directly.

After you submit payment, you receive a confirmation number immediately. Keep this number — it proves you paid and when. If you need to dispute a payment or check whether it posted, the Comptroller's office uses this confirmation number to locate your transaction.

Mailing a check or money order

If you prefer to pay by mail, you send a check or money order with a payment voucher to the address listed on your tax notice or on the Comptroller's website. The voucher includes your tax ID, the tax year, and the amount owed — this information helps the state match your payment to your account. Without the voucher, your payment may be delayed or misapplied.

Mail payments take longer to reach the state than online payments. A check mailed on April 10 may not post until April 20 or later, depending on postal delays and processing time at the Comptroller's office. The postmark date is what matters for the deadline — if your envelope is postmarked by April 15, the payment is considered on time even if it arrives later. However, if the check does not clear your bank by the deadline, you are still responsible for any interest or penalties that accrue.

Write your Social Security number or tax ID on the check itself, not just on the voucher. If the voucher is lost in transit, the number on the check helps the state identify your account.

Quarterly estimated tax payments for self-employed filers

If you are self-employed, a freelancer, or have income that is not subject to employer withholding, Maryland requires you to make quarterly estimated tax payments. These payments cover both federal and state taxes and are due on June 15, September 15, December 15, and April 15. Each payment should represent roughly one-quarter of your expected annual tax liability.

You can make quarterly payments online through the Comptroller's portal using the same method as a lump-sum payment, or by mail with a voucher. The state does not send you a bill or reminder for quarterly payments — it is your responsibility to calculate the amount owed and submit it by the deadline. If you underpay or miss a payment, interest and penalties begin to accrue immediately.

To estimate your quarterly payment, add up your expected income for the year, subtract deductions, and multiply by Maryland's tax rate (which varies by income level). If you are unsure of the amount, you can pay a conservative estimate and adjust when you file your annual return — overpayment is refunded or credited to the next year's taxes.

What happens if you pay late

If your payment does not reach the Comptroller's office by April 15, interest begins to accrue at a rate set by the state each year. The interest rate is typically between 8 and 10 percent annually, compounded daily. A penalty of 10 percent of the unpaid tax is also added if you do not pay by the deadline, though the penalty is waived if you can show reasonable cause for the delay.

If you cannot pay the full amount by April 15, you can still file your return on time to avoid the failure-to-file penalty. You will owe interest and the failure-to-pay penalty on the unpaid balance, but filing on time limits the penalties you face. You can also contact the Comptroller's office to discuss a payment plan if you owe a large amount — the state offers installment agreements for taxpayers who cannot pay in full.

Late payments do not affect your federal tax status directly, but if you owe Maryland taxes, the state can place a lien on your property or intercept your federal tax refund to cover the debt. This process can take several months, so addressing unpaid taxes early prevents these complications.

Checking your payment status and account balance

You can log into the Comptroller's online portal at any time to see your account balance, payment history, and the status of any pending payments. The portal shows the date each payment posted, the amount, and which tax year it was applied to. If you submitted a payment and want to confirm it arrived, this is where you check.

If you have questions about your balance or a payment does not appear within two business days of the deadline you were given, contact the Comptroller's Individual Income Tax Section by phone or mail. Have your confirmation number ready if you paid online, or your check number if you paid by mail. The office can tell you whether your payment posted and, if not, help you trace where it went.

Frequently Asked Questions

Can I pay Maryland taxes with a credit card?

No, the Comptroller's portal does not accept credit cards directly. You can pay only from a U.S. checking or savings account. Some credit card companies allow you to pay bills through their own bill-pay systems, but you would be paying from your bank account, not charging the tax to the card.

What if I file an extension — do I still have to pay by April 15?

Yes. An extension to file your return does not extend the payment deadline. Taxes owed are due by April 15 regardless. If you file an extension but do not pay by April 15, you owe interest and penalties on the unpaid amount, even though you have until October 15 to file the return itself.

How do I know if my employer is withholding the right amount of Maryland tax?

Check your pay stub — it should show Maryland state tax withheld each pay period. If you receive a large refund every year, your employer is withholding too much. If you owe money at tax time, your employer is withholding too little. You can adjust your withholding by submitting a new W-4 form to your employer's payroll department.

What if I moved out of Maryland — do I still owe state income tax?

If you lived in Maryland for part of the tax year and moved out, you owe Maryland tax only on income earned while you were a resident. You file a part-year resident return and report income for the months you lived in the state. If you moved to another state, you may owe taxes to that state as well, depending on where you worked and earned income.

Can I set up automatic payments so I do not have to remember the deadline?

The Comptroller's portal does not offer automatic recurring payments, but you can set a reminder on your phone or calendar for April 10 each year. Some banks' bill-pay systems allow you to schedule a one-time payment to the Comptroller's address, which you can set up a few days before the deadline to account for mail delays.