Edit: I misunderstood the situation and will amend but leave original answer
below with comment.
For an LLC to stop being treated as S Corp, file Form CT-6.1 with NYS DTF.
For the IRS, there is no form(IRS source). Instead you have to file a statement to the service center where you file tax returns.
The statement should state:
- The corporation revokes the election made under Section 1362(a)
- Name of the shareholder(s),
- Address of the shareholder(s),
- Taxpayer identification number of the shareholder(s),
- The number of shares of stock owned by the shareholder(s),
- The date (or dates) on which the stock was acquired
- The date on which the shareholder's taxable year ends
- The name of the S corporation
- The S corporation's EIN
- The election to which the shareholder(s) revokes
- The statement must be signed by the shareholder(s) under penalties of perjury
- Signature and consent of shareholder(s) who collectively own more than 50% of the number of issued and outstanding stock of the corporation, whether voting or non-voting)
- Indication of the effective date of the revocation (or prospective date)
- Signature of person authorized to sign return
My first answer below applied to S Corps wanting to become LLC, which is not what was asked:
New York does not allow a corporation to change into an LLC. Instead you must create a new LLC by filing Articles of Organization and then have the S Corp assumed by the new LLC by filing a Certificate of Merger. Both filings are with the NY Department of State. If this is your livelihood, please talk to a lawyer.