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A Message from the Supervisor

“Welcome to Islip, the 3rd largest town in New York State, but with an endearing small town feel. We are so proud of our town…our beaches, golf courses, marinas, parks, housing opportunities for all, businesses, industrial parks, healthcare and educational institutions including our own Islip MacArthur Airport that provides many job opportunities. I sincerely hope you find this website helpful.” Angie


  1. When does tax collection begin / when do I receive my bill?

    • Collection begins and tax bills are mailed around the second week of December.

    • Online payments are available in the same time frame.

    • If a mortgage company and/or lending institution is paying the property taxes on your behalf, then you will not receive a bill in December. You will receive a statement in February after payment of the 1st half taxes and again in July after the payment of your 2nd half taxes.

  2. How many times a year do you send out the Tax Bill?

    • Once per year, around the second week in December.

  3. When is my payment due?

    • Your taxes are due and payable in full on or before January 10th. If you are unable to pay in full, then, to avoid penalty, the 1st half must be paid on or before January 10th and the 2nd half, on or before May 31st.

  4. Can I make partial payments on my property taxes?

    • Yes, a minimum partial payment of $200 (plus penalty when applicable) can be made in person or through the mail anytime during collection until May 31st.

  5. Can I pay my taxes early?

    • No. The Tax Receivers office does not know how much your taxes are until we receive the Warrant from the Suffolk County Legislature in early December.

  6. What if I pay my taxes late?

    • If you do not make the January 10th deadline, please follow the penalty schedule below:

      December 1st – January 10th No Penalty
      After January 10th 1% Penalty
      After February 10th 2% Penalty
      After March 10th 3% Penalty
      After April 10th 4% Penalty
      May 11th to May 31st 5% Penalty

    • Any outstanding balance after May 31st is payable to the Suffolk County Comptroller in Riverhead, NY. Please contact their office for payment information.

  7. When I look at my Tax Bill, it shows the former owner. Why is that? Should I be worried?

    • The tax bill that is created in December, is based upon ownership information as of March 1st of the same year. Therefore, if you purchased your property after March 1st, that is why the former owners' information still shows. It can take up to 6 months for it to change in our system from the date of your closing.

    • In this case during the following December, when the next tax bill is created, your information will show when we produce that year’s tax bill

  8. What if I didn’t receive my tax bill in the mail, do I have to pay my property taxes or any late fees?

    • Yes. If you are the owner of a property, you are responsible for your taxes even if you do not receive your bill.

  9. How do I obtain a copy of a Tax Bill?

    • If you are the property owner and you have lost or misplaced your tax bill, please visit our Payment Portal site, Create an account and you can download/print an un-official copy of your tax bill. Otherwise, you can visit us in person for an official copy. There is no charge to the property owner for a duplicate copy.

    • If you are NOT the property owner you can request an official copy in person or by mail. The cost is $5.00 p/parcel.

  10. I am a friend, attorney, banker, broker etc., and am working on behalf of the owner, do I have to pay the $5.00 duplicate bill fee?

    • Yes. Only the owner of the property is exempt from the $5.00 duplicate bill fee. If you are working on behalf of the owner, you are a 3rd party and are subject to that fee.

  11. The payment coupon asks for my telephone number, why do you need it?

    • Sometimes there may be an issue with your payment. In lieu of mailing the paperwork back to you, leaving a contact telephone number gives us the ability to potentially solve a problem over the phone. We do not share your telephone number.

  12. How do I change my mailing address?

    • Please visit the “Forms” sections of the website and complete the Change of Address.

  13. I just finished paying off my mortgage, do I need to do anything with the Office of the Receiver of Taxes?

    • Congratulations! Please call our office, so we can update our records.

  14. Where can I find the Item Number or Tax Map Number to a property?

    • If you have a copy of a tax bill and/or statement, the Item Number is located in the upper right corner of the document. The Tax Map Number is located on the left side in the top 1/3 of the document.

    • You can also find that information by visiting,

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