An oil terminal (also called a tank farm, tankfarm, oil installation or oil depot) is an industrial facility for the storage of oil, petroleum and petrochemical products, and from which these products are transported to end users or other storage facilities. An oil terminal typically has a variety of above or below ground tankage; facilities for inter-tank transfer; pumping facilities; loading gantries for filling road tankers or barges; ship loading/unloading equipment at marine terminals; and pipeline connections.

Originally, open pits and cubic reservoirs were used for industrial oil storage.

The vertical cylindrical steel reservoir [ru] structure was pioneered by Russian engineer Vladimir Shukhov during his work for Branobel oil company. He published an article "Mechanical structures in oil industry" ("Механические сооружения нефтяной промышленности") in 1883, mathematically proving that cylindrical shape would require the least amount of steel, modelling structural stresses specific to oil storage. Shukhov also developed construction methods, including tables that allowed to calculate required amount of steel and components depending on the reservoir size and type. By 1890, 130 vertical cylindrical reservoirs using Shukhov design were built in Russia.

Oil terminals may be located close to, or be part of, oil refineries; or be located in coastal locations where marine tankers can discharge or load cargo. Some terminals are connected to pipelines from which they draw or discharge their products. Terminals can also be served by rail, barge and road tanker (sometimes known as "bridging"). Oil terminals are also located near cities from which road tankers transport products to petrol stations or other domestic, commercial or industrial users.

In many oil terminals there are no facilities for processing or other product transformation on site. The products from a refinery which are stored in the terminal are in their final form suitable for delivery to customers. Blending of products may be undertaken, and additives may be injected into products, but there is usually no manufacturing plant on site. Modern terminals have a high degree of site automation.

Marine oil terminals have jetties to provide a deep water mooring for tankers. Jetties have loading/unloading arms for transferring cargo to/from ship to shore. Facilities for vapor recovery may be provided.

Some oil terminals receive crude oil production from offshore installations. Crude oil received by pipeline may have been 'spiked' with natural gas liquids (NGL), and is known as live crude. Such oil needs to be processed or stabilised to remove the lighter fractions such as ethane, propane and butane to produce a dead or stabilised crude that is suitable for storage and transport. Such oil terminals may include processing facilities to treat the oil to achieve an oil Reid vapor pressure (RVP) of 10 to 12 psi (70 to 82 kPa). The process facilities include oil heaters to warm the oil which then routed to separator vessels. In the separators the lighter fractions flash off from the oil and are further processed to separate them into their individual components. The now stabilised oil can be routed to storage and then sold or sent for further processing.

Most airports also have their own dedicated oil depots (usually called "fuel farms") where aviation fuel (Jet A or 100LL) is stored prior to being discharged into aircraft fuel tanks. Fuel is transported from the depot to the aircraft either by road tanker or via a hydrant system.