12 Miss. Code. R. 3-2.1-600.43
If a bid is more than $50,000, a Bidder must have a Certificate of Responsibility Number in order to submit a bid, enter into a Contract, or otherwise engage in or continue in this State in the business of a public Contractor. Any Contractor submitting a bid for construction of public works or public projects without a Certificate of Responsibility Number is guilty of a misdemeanor. [Mississippi Code 1972, Annotated, Section 31-3-21(2)]
If the bid is less than $50,000, a Certificate of Responsibility Number is not required. The bidder must, however, make a statement on the outside/exterior of the envelope to the effect that the bid enclosed does not exceed $50,000. [Mississippi Code 1972, Annotated, Section 31-3-21(2)]
12 Miss. Code. R. 3-2.1-600.43