2025 Printable Template
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Form last updated: 03/2024. Please verify this is the current version before use.
Easily complete & submit your ST-121 form
Follow these simple steps to fill, sign, and send your ST-121 form online.
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How to fill out a ST-121 online?
Follow these steps to complete your ST-121 form online.
Step 01
Access Form ST-121 from the New York State Department of Taxation and Finance website.
Step 02
Fill in the purchaser's identification details.
Step 03
Enter the seller's details.
Step 04
Indicate the nature of the property or service being acquired.
Step 05
Sign the form.
Step 06
Review the information for accuracy.
What is a ST-121 used for?
Who needs to fill out a ST-121 form
What is Form ST-121?
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