Mechanical Contractor Registration expires annually on August 31st.  Per Section 20-341s of the Connecticut General Statutes,  “Mechanical contractor” means any corporation, association, firm, partnership or other business organization regularly offering to the public the services of its employees in plumbing andpiping work or in heating, piping and cooling work, but does not mean any corporation, association, firm, partnership or other business organization which performs such work exclusively on single family or multifamily private residences or dwellings consisting of not more than four units or which employs less than ten persons licensed to perform plumbing and piping work or heating, piping and cooling work in accordance with the provisions of chapter 393, or any corporation, association, firm, partnership or other business organization which is engaged in the installation, repair, alteration, or replacement of sewer lines, storm drainage lines or water lines and services. The term “mechanical contractor” does not include an individual licensed pursuant to chapter 393 of the Connecticut General Statutes. Registration is required for all businesses or individuals offering services to the public in plumbing and piping work or in heating, piping and cooling work employing ten (10) or more licensed persons.