There are six categories of membership in the institute. These are;
- Full Member: This is a person who has passed the Qualifying examinations for persons intending to work for Legal metrology authorities as inspectors and practising in the legal metrology field or a related consumer protection field.
- Associate Member: Shall be a person who is a practicing Assistant Legal Metrologist
- Student Member: This is a person who is undergoing training in legal metrology. Membership in this category shall be limited to a period of five years without the option of re-admission upon expiry.
- Observer Member: This is a company or institution engaged in as manufacture, overhaul or servicing of legal metrology instruments
- Fellow : This is a Full Member who:
(i) has made invaluable contribution to the legal metrology profession or the Institute, and
(ii) has satisfied such requirements as may be prescribed by the Council, and
(iii) is recommended by the Council to the General Assembly for admission into fellowship.
Honorary Member: This is a person of eminence in the field of standardization, scientific metrology and accreditation services whose membership would, in the opinion of the Council, further the aims of the Institute