A. If your business is an LLC that is taxed as a partnership but you received a delinquency notice for corporation business tax (Form CT-1120), there may be an error in your registration. Send a letter with a copy of the Connecticut or federal partnership return for the year in question to:
Department of Revenue Services
Registration Maintenance Unit
PO Box 2937
Hartford CT 06104-2937
LLCs that are taxed as partnerships are required to file Form OP-424, Business Entity Tax Return and Form CT-1065/CT-1120SI, Composite Income Tax Return. For more information on LLC filing requirements, visit our webpage for Partnerships, LLCs and Other Pass-Through Entities.
This answer is intended to provide general information concerning a frequently asked question about a current position, policy, or practice associated with the taxes administered by the Connecticut Department of Revenue Services. It may include an informal interpretation of Connecticut tax law by the Department of Revenue Services (DRS). However, it is not intended to serve as a legal ruling.