Standard Oil of Ohio

Under the name "The Standard Oil Company (Ohio)", the company was established as a separate business after the antitrust breakup the oil conglomerate's monopoly in 1911. It operated service stations under the 'Sohio' brand name in Ohio but was prohibited in using the 'Standard' name in other states. In nearby states, it used the Boron brand name (introduced in 1954) instead, but with an otherwise-similar logo. Wallace Trevor Holliday was President of the company from 1928 to 1949 and Chairman of the Board from 1949 until his death on November 7, 1950.

In 1968, Sohio's CEO, Charles E. Spahr (Charlie), arranged a merger with BP. It was announced as Standard's acquisition of BP's North American interests in exchange for BP receiving 25% of Sohio's stock. However, the contract included a stipulation that BP would assume majority interest when Standard's share of production from the Prudhoe Bay oilfield in Alaska reached 600,000 barrels per day (95,000 m3/d). That occurred in 1978, and BP then took control of Standard Oil. The U.S. operations were unified under the BP America corporate name.

By 1991, BP had rebranded all Sohio and Boron retail stations as 'BP', except for some marine fuel outlets.

In 2011, a BP station in Steubenville, Ohio, that had originally opened as a Sohio station in 1946 ended fuel sales and was restored to 1970s vintage Sohio colors as a museum for Sohio. The site has vintage (inoperable) Sohio pumps and other Sohio memorabilia. The garage itself remains active.

Hospitality Motor Inns

Hospitality Motor Inns, a wholly owned Sohio subsidiary, operated 11 motor inns in Ohio and surrounding states The company was formed in 1963 as a Sohio subsidiary. Hospitality became a publicly held company when Sohio sold off 51% of the company to the public. Sohio sold its remaining interest of the chain to Hosmin, Inc., in 1978.

ProCare

In the 1980s, as many gas stations began converting their vehicle service bays into convenience stores, Sohio wished to continue performing auto maintenance by launching a specialty auto repair shop. Called Sohio ProCare, these shops were often located near Sohio stations that now had convenience stores instead of auto service and were more specialized compared to traditional auto garages located at gas stations. The locations were mostly in Ohio, but Sohio did expand the concept into Pennsylvania and North Carolina, where they were known as "Boron ProCare". Also, unlike many Sohio stations, the ProCare locations were owned and operated directly by Sohio. Commercials for ProCare often featured M*A*S*H actor Gary Burghoff as "That Sohio Guy", as part of a larger Sohio advertising campaign featuring Burghoff. Burghoff himself would stay with BP for a time as a spokesperson after BP converted Sohio and its other brands to BP.

BP retained ProCare following its absorption of Sohio, rebranding it as "BP ProCare" and changing the colors in its logo to match BP. BP continued to operate it until selling the chain to a private investment group in 1999, at which point the shops were simply called ProCare without an oil company prefix and its logo reverted to its Sohio-era colors. Following a bankruptcy under the private investment group's ownership, ProCare would ultimately be acquired by Monro Muffler Brake in 2006, and converted the locations to its own brands.