Fluorescent lampholders specially designed for the various types of lamp bases are required to support fluorescent lamps and to provide the electrical connections needed. For the preheat and rapid start bipin base, the original and widest used lampholder is the twist-turn type.

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Spring pressure push-pull lampholders are also available for bipin base lamps.

Lampholders for Slimline lamps are designed for single pin bases. When the lamp is installed, the pin of one end is inserted in the small hole in the high voltage lampholder. This is the one with the spring plunger. The lamp is positioned to compress the spring that permits the other end of the lamp to be inserted in the fixed holder. This is the low voltage end of the circuit and contains the open circuiting mechanism that breaks the contact to the ballast when the lamp is removed. High Output and Very-Hi Output lamps are made with recessed double contact bases and require specially designed push-pull lampholders.

Fluorescent lamp dimensions are controlled within extremely close limits. Lamp holder spacing, however, must be correct or lamps on the long side of the permissible tolerance will jam. Those on the short side may make poor contact and, in extreme cases, may drop out. Published nominal lamp lengths include the lamp and two standard lampholders. The proper spacing and tolerance for other designs should be obtained from the manufacturer.