Photo of the EMC E2 locomotive LA-1 from the Union Pacific train "City of Los Angeles" from a 1944 Union Pacific Railroad ad.

(Union Pacific Railroad., Public domain, via Wikimedia Commons)



The Union Pacific Railroad (reporting marks UP, UPP, UPY), legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over 32,200 miles (51,800 km) routes in 23 U.S. states west of Chicago and New Orleans. Union Pacific is the second largest railroad in the United States after BNSF, with which it shares a duopoly on transcontinental freight rail lines in the Western, Midwestern and West South Central United States.

Founded in 1862, the original Union Pacific Rail Road was part of the first transcontinental railroad project, later known as the Overland Route. Over the next century, UP absorbed the Missouri Pacific Railroad, the Western Pacific Railroad, the Missouri–Kansas–Texas Railroad and the Chicago, Rock Island and Pacific Railroad. In 1995, the Union Pacific merged with Chicago and North Western Transportation Company, completing its reach into the Upper Midwest. In 1996, the company merged with Southern Pacific Transportation Company, itself a giant system that was absorbed by the Denver and Rio Grande Western Railroad. The Union Pacific Railroad is the principal operating company of the Union Pacific Corporation, which are both headquartered at the Union Pacific Center, in Omaha, Nebraska.


A map of the Union Pacific Railroad as of 2008, with trackage rights in purple.

(No machine-readable author provided. NE2 assumed (based on copyright claims)., Public domain, via Wikimedia Commons)



Union Pacific in the 19th century

The original company, the "Union Pacific Rail Road", incorporated on July 1, 1862, under the Pacific Railroad Act of 1862. President Abraham Lincoln had approved the act, which authorized railroad construction from the Missouri River to the Pacific to ensure the stability of the Union throughout the American Civil War, but construction did not complete until after that conflict's conclusion. The resulting track ran westward from Council Bluffs, Iowa to meet in Utah the Central Pacific Railroad line, which had been constructed eastward from Sacramento, California. The combined Union Pacific–Central Pacific line became known as the first transcontinental railroad and later the Overland Route.

The line was constructed primarily by Irish labor who had learned their craft during the recent Civil War. Under the guidance of its dominant stockholder Dr. Thomas Clark Durant, the namesake of the city of Durant, Iowa, the first rails were laid in Omaha. The two lines were joined at Promontory Summit, Utah, 53 miles (85 km) west of Ogden on May 10, 1869, hence creating the first transcontinental railroad in North America.

Subsequently, the UP purchased three Mormon-built roads: the Utah Central Railroad extending south from Ogden to Salt Lake City, the Utah Southern Railroad extending south from Salt Lake City into the Utah Valley, and the Utah Northern Railroad extending north from Ogden into Idaho.

The original UP was entangled in the Crédit Mobilier scandal, exposed in 1872. As detailed by the New York Sun, Union Pacific's largest construction company, Crédit Mobilier, had overcharged Union Pacific; the railroad would then pass the inflated costs on to the United States government. To convince the federal government to accept the increased costs, Crédit Mobilier had bribed multiple congressmen. Several prominent UP board members (including Durant) had been involved in the scheme. The ensuing financial crisis of 1873 led to a credit crunch, but not bankruptcy.

As boom followed bust, the Union Pacific continued to expand. A new company, with dominant stockholder Jay Gould, purchased the old on January 24, 1880. Gould already owned the Kansas Pacific (originally called the Union Pacific, Eastern Division, though in essence a separate railroad), and sought to merge it with UP. Through that merger, the original "Union Pacific Rail Road" transformed into "Union Pacific Railway".

Extending towards the Pacific Northwest, Union Pacific built or purchased local lines to reach Portland, Oregon. Towards Colorado, it built the Union Pacific, Denver and Gulf Railway: a system combining narrow-gauge trackage into the heart of the Rockies and a standard gauge line that ran south from Denver, across New Mexico, and into Texas.

The Union Pacific Railway would later declare bankruptcy during the Panic of 1893. The resulting corporate reorganization reversed Gould's name change: Union Pacific "Railway" merged into a new Union Pacific "Railroad".


The Last Spike, by Thomas Hill (1881). The painting depicts the ceremony of the driving of the "Last Spike" at Promontory Summit, UT, on May 10, 1869, joining the rails of the Central Pacific Railroad and the Union Pacific Railroad. It is worth noting that some of the people depicted in the painting were not at the Gold Spike ceremony (e.g., Collis P. Huntington, Charles Crocker, Edwin B. Crocker, Theodore Judah and Mark Hopkins). Only two of the members of the Central Pacific board of directors were present: Leland Stanford and Charles Marsh (who are depicted in the painting). (California State Railroad Museum, Public domain, via Wikimedia Commons)


Directors of the Union Pacific Railroad gather on the 100th meridian, which later became Cozad, Nebraska, about 250 miles (400 km) west of Omaha in the Nebraska Territory, in October 1866. The train in the background awaits the party of Eastern capitalists, newspapermen, and other prominent figures invited by the railroad executives. (John Carbutt, Public domain, via Wikimedia Commons)

Union Pacific in the 20th century

In the early 20th century, Union Pacific's focus shifted from expansion to internal improvement. Recognizing that farmers in the Central and Salinas Valleys of California grew produce far in excess of local markets, Union Pacific worked with its rival Southern Pacific to develop a spoilage-resistant rail-based transport system. These efforts came culminated in the 1906 founding of Pacific Fruit Express, soon to be the world's largest lessee of refrigerated railcars.

Meanwhile, Union Pacific worked to construct a faster, and more direct substitute for the original climb to Promontory Summit. In 1904, the Lucin cutoff opened, reducing curvature and grades. The original route would eventually be stripped of track in 1942 to provide war scrap.

To attract customers during the Great Depression, Union Pacific's chairman W. Averell Harriman simultaneously sought to "spruce up" the quality of its rolling stock and to make its unique locations more desirable travel destinations. The first effort resulted in the purchase of the first streamlined train: the M-10000. The latter resulted in the Sun Valley ski resort in central Idaho; it opened in 1936 and finally was sold in 1964. Despite the fact that the M-10000 and its successors were among the first diesel locomotives, Union Pacific completed dieselization relatively late. In 1944, UP finally received delivery of its last steam locomotive: Union Pacific 844.

As the 20th century waned, Union Pacific recognized—like most railroads—that remaining a regional railroad would only lead to bankruptcy. On December 31, 1925, UP and its subsidiaries operated 9,834 miles (15,826 km) routes and 15,265 miles (24,567 km) tracks; in 1980, these numbers had remained roughly constant (9,266 route-miles and 15,647 track-miles). But in 1982, UP acquired the Missouri Pacific and Western Pacific railroads, and 1988, the Missouri–Kansas–Texas. By 1993, Union Pacific had doubled its system to 17,385 miles (27,978 km) routes.

By then, few large (class I) railroads remained. The same year that Union Pacific merged with the Chicago and North Western (1995), Burlington Northern and ATSF announced merger plans. The impending BNSF amalgamation would leave one mega-railroad in control of the west. To compete, UP merged with Southern Pacific, thereby incorporating D&RGW and Cotton Belt, and forming a duopoly in the West. The merged railroad took the Union Pacific name. As of 1999, the UP had 33,705 miles (54,243 km) of track, about 33,000 employees, nearly 7,000 locomotives and over 155,000 rail cars.


Ogden, Utah yard.

(The original uploader was N2xjk at English Wikipedia., CC BY-SA 3.0 <>, via Wikimedia Commons)



The Union Pacific system includes hundreds of yards. Most are flat yards used for local switching. Other types of yards include intermodal terminals and hump yards. Most UP intermodal terminals are typically ports, but UP also has inland terminals for transfers to trucks, such as the terminal in San Antonio that opened in 2009 or the one in Santa Teresa, New Mexico, that opened in 2014.

Hump yards

In 2006, Union Pacific had 11 major active hump yards:

  • Bailey Yard in North Platte, Nebraska
  • Beaumont Yard in Beaumont, Texas
  • Davidson Yard in Fort Worth, Texas
  • Davis Yard in Roseville, California
  • Roseville Rail Yard
  • Englewood Yard in Houston, Texas
  • Gateway Yard in East St Louis, Illinois, owned by subsidiary Alton and Southern Railway
  • Livonia Yard in Livonia, Louisiana
  • North Little Rock Yard in North Little Rock, Arkansas
  • Proviso Yard in Northlake, Illinois, owned by Chicago and North Western Transportation Company until 1995
  • Strang Yard in La Porte, Texas
  • West Colton Yard in Bloomington, California

In the late 2010s, Union Pacific began deactivating hump yards in favor of flat switching. In this, Union Pacific followed the industry-wide trend towards Precision Scheduled Railroading (PSR); railway executive Hunter Harrison explained that under PSR, few yards receive enough variegated traffic to necessitate a hump. Union Pacific also closed facilities in Kansas City ("Neff yard"), Hinkle, Oregon, and Pine Bluff, Arkansas in 2019.


Union Pacific No. 9214, a GE Dash 8-40C, shows the standard UP diesel locomotive livery on May 10, 1991. Photo by Sean Lamb.

(The original uploader was Slambo at English Wikipedia., CC BY-SA 2.0 <>, via Wikimedia Commons)


Locomotives and rolling stock

Union Pacific has owned some of the most powerful locomotives. These include members of the Challenger-type (including the 3985), and the Northern-type (including the 844), as well as the Big Boy steam locomotives (including the 4014). Union Pacific ordered the first diesel streamliner, the largest fleet of turbine-electric locomotives in the world, and the largest diesel locomotives ever built (including 6936).


General Electric ET44AH locomotive No. 2668 of the Union Pacific Railroad.

(Flickr user Tyler Silvest Wikideas1 (talk) 21:43, 7 November 2016 (UTC), CC BY 2.0 <>, via Wikimedia Commons)


Paint and colors

The yellow paint scheme was introduced in the spring of 1934. Engineers claimed the visibility of yellow would reduce grade crossing accidents. In 1941, UP introduced its yellow and gray color scheme with red highlights, which remains in use today.

The middle two-thirds of the locomotive body is painted Armour Yellow, a color used by Armour and Company on the packaging of its meat products. A thin band of Signal Red divides this from the Harbor Mist Gray (a light gray) used for the body and roof above that point. There is also a thin band of Signal Red along the bottom of the locomotive body, but this color has gradually become yellow as new Federal Railroad Administration (FRA) regulations for reflectorized tape came into effect in 2005; the trucks (painted Aluminum from 1955 to 1982), underframe, fuel tanks and everything else beneath that line are also Harbor Mist Gray. Lettering and numbering are in Signal Red, with black outlines. Most locomotives have white-outlined blue "wings" on the nose, on either side of the renowned shield featuring white lettering on a blue background and, below it, red and white vertical stripes. Beginning in early 2002, a number of units were repainted with a large, billowing American flag with the corporate motto "Building America" on the side, where the 'UNION PACIFIC' lettering is normally positioned.


A former Southern Pacific GP38-2 locomotive renumbered with UP "patch" markings.

(Morven, CC BY-SA 3.0 <>, via Wikimedia Commons)


Merger partner locomotives

Until 2017, UP operated some locomotives still in the paint scheme of their former railroads. In addition, some locomotives were renumbered by UP, varying in the degree of the previous railroads' logos being eradicated, but always with a yellow patch applied over the locomotive's former number and a new UP number applied on the cab. That allowed UP to number locomotives into its roster without spending the time and money necessary to perform a complete repaint. In May 2015, UP rostered 212 "patches", consisting of:

  • 22 Chicago and North Western (whose CNW logos have been hidden by the "patches")
  • 174 Southern Pacific (AC4400CW, GP40-2, MP15AC, and GP60)
  • 14 St. Louis Southwestern (GP60)
  • 2 Denver and Rio Grande Western (GP60)
  • While not technically a predecessor locomotive in the traditional sense, UP also rostered a single SD40-2 (3564, since retired) still in the 1970s paint scheme, not counting DDA40X No. 6936, which was part of the Union Pacific Heritage Fleet until 2022.

In 2017, Union Pacific decided to repaint all locomotives which were not in the current corporate colors. As of March 2018, only 41 locomotives remained unpainted.


Union Pacific No. 5391, approaching bridge at Multnomah Falls, Oregon, shows the white-outlined blue "wings" on the nose. (Khamar, CC BY-SA 3.0 <>, via Wikimedia Commons)

Union Pacific No. 5391, approaching bridge at Multnomah Falls, Oregon, shows the white-outlined blue "wings" on the nose. (CreeperBoy844, CC BY-SA 4.0 <>, via Wikimedia Commons)


Commemorative color schemes

From the second half of 2005 to the summer of 2006, UP unveiled a new set of six EMD SD70ACe locomotives in "Heritage Colors", painted in schemes reminiscent of railroads acquired by the Union Pacific Corporation since the 1980s. The engine numbers match the year that the predecessor railroad became part of the Union Pacific system. The locomotives commemorate the Missouri Pacific with UP 1982, the Western Pacific with UP 1983, the Missouri–Kansas–Texas with UP 1988, the Chicago and North Western with UP 1995, the Southern Pacific with UP 1996, and the Denver and Rio Grande Western with UP 1989.

In October 2005, UP unveiled SD70ACe 4141, commissioned in honor of George Bush. The locomotive has "George Bush 41" on the sides and its paint scheme resembles that of Air Force One. It was sent into storage in 2007, but returned in 2018 to power Bush's funeral train. It was donated to the George H.W. Bush Presidential Library and Museum on November 8, 2019.

On March 31, 2010, UP dedicated a specially painted GE ES44AC locomotive commemorating the centennial of the Boy Scouts of America.

On September 28, 2010, UP dedicated a specially painted GE ES44AC locomotive, as a tribute to Susan G. Komen for the Cure.

On October 19, 2017, Union Pacific unveiled SD70AH 1943, "The Spirit of the Union Pacific", which is painted in a scheme to honor the United States armed forces.

On June 6, 2019, Union Pacific unveiled SD70ACe 1111, the "Powered By Our People" unit.

In April 2021, Union Pacific repainted an SD70M into a commemorative paint scheme called "We Are ONE" to honor Juneteenth and Pride Month.

UP also has a collection of locomotives painted for Operation Lifesaver, a rail safety organization founded in 1970.


2013 locomotive roster

As of October 2013, the Union Pacific had 8,185 locomotives on its active roster. The locomotive fleet consists of 43 different models and had an average age of 17.8 years. According to Union Pacific, this is the largest fleet of diesel-electric locomotives in the US.


Big Boy No. 4014 passes through Friesland, Wisconsin, on July 25, 2019.

(Mark Loewe from Huntley, IL, CC BY 2.0 <>, via Wikimedia Commons)


Heritage equipment

Union Pacific continues to use a small number of "heritage" steam locomotives and early streamlined diesel locomotives. This equipment is used on special charters (excursions).


One of the 20 new 2,000 horsepower (1,500 kW) "Green Goat" locomotives manufactured for Union Pacific's "Green" Fleet by Railpower Technologies.

(Bryan Flint, CC BY-SA 3.0 <>, via Wikimedia Commons)


Low-emissions locomotives

Union Pacific maintains a fleet of low-emissions locomotives. Most are used in Los Angeles basin rail yards, to satisfy an air quality agreement with the local authorities.


Two UP AC4400CWs, including an ex-CNW unit, lead a typical empty coal train west at Belvidere, Nebraska, in July 2015.

(Augy8400, CC BY-SA 4.0 <>, via Wikimedia Commons)


Facts and figures

According to UP's 2007 Annual Report to Investors, at the end of 2007 it had more than 50,000 employees, 8,721 locomotives, and 94,284 freight cars.

Broken down by specific type of car, owned and leased:

  • 35,437 covered hoppers
  • 12,272 boxcars
  • 18,647 open-top hoppers
  • 13,780 gondolas
  • 14,148 "other" types of cars

In addition, it owns 6,950 different pieces of maintenance of way work equipment. At the end of 2007, the average age of UP's locomotive fleet was 14.8 years, the freight car fleet 28 years.

UP was ranked 134th on the 2019 Fortune 500 list of the largest United States corporations by revenue and had 41,967 employees. The president of Union Pacific since 2015 is Lance Fritz.

Union Pacific has been rated the worst company to work for in 2019 by, citing CEO Lance Fritz's 12% approval rating and the 22% recommendation rating from


A C&NW North Line train stops at Wilmette, Illinois, in 1963.

(Photo by Roger Puta, courtesy Marty Bernard, railfan 44, Public domain, via Wikimedia Commons)


Passenger service

Commuter services

When Union Pacific bought out the Chicago & North Western in 1995, it inherited the railroad's Metra commuter rail services in the Chicago metropolitan area: the UP/North, UP/Northwest, and UP/West lines, all of which operate from the Ogilvie Transportation Center (the former North Western Station–a name still used by many Chicago residents). In order to ensure uniformity across the Chicago area commuter rail system, trains are branded as Metra services and use Metra equipment. However, Union Pacific crews continue to operate the trains under a purchase-of-service agreement.


Wine label, Roma Wine Company, bottled for Union Pacific RR circa 1940s.

(California Historical Society, No restrictions, via Wikimedia Commons)


Former services

Between 1869 and 1971, Union Pacific operated passenger service throughout its historic "Overland Route". These trains ran between Chicago and Omaha on the Chicago & Northwestern trackage starting in 1936. Disputes over trackage rights and passenger revenues with the C&NW prompted the UP to switch to the Milwaukee Road for the handling of its streamliner trains between Chicago and Omaha beginning in late 1955. The last intercity passenger train operated by UP was the westbound City of Los Angeles, arriving at LA Union Station on May 2. Since then, Union Pacific has satisfied its common carrier requirements by hosting Amtrak trains.


Hosted trains

Many Amtrak and commuter rail routes use Union Pacific rails. This list excludes the commuter services the company directly operates in Chicago (see above).

Amtrak Cascades
California Zephyr
Capitol Corridor
Coast Starlight
Lincoln Service
Missouri River Runner
Pacific Surfliner
San Joaquin
Sunset Limited
Texas Eagle

Commuter trains
Altamont Corridor Express
Riverside Line
Ventura County Line
RTD commuter rail
G Line
Trinity Railway Express



Union Pacific and Norfolk Southern are the largest owner-partners of Equipment Management Pool (EMP), a domestic freight interline intermodal freight transport service that rents and moves more than 35,000 53-foot containers and chassis throughout North America. Other partners in the freight company include Canadian National Railway, I&M Rail Link, Iowa Interstate Railroad, Wisconsin Central Ltd., and Kansas City Southern Railway. In 2022, Canadian Pacific Railway was dropped from the pool, leaving CN as the only Canadian member.


The Union Pacific Railroad Museum.

(America's Power, CC BY 2.0 <>, via Wikimedia Commons)


Union Pacific Railroad Museum

The Union Pacific Railroad Museum is a former Carnegie library in Council Bluffs, Iowa that houses artifacts, photographs, and documents that trace the development of the railroad and the American West. The company pays upkeep on the privately owned building, which houses part of Union Pacific's corporate collection, one of the oldest in the United States. Holdings include weapons from the late 19th and 20th centuries, outlaw paraphernalia, a sampling of the immigrants' possessions, and a photograph collection comprising more than 500,000 images.


Other Topics regarding Union Pacific

Click on a topic below to see other articles about the Union Pacific.

Notable accidents

Community responsibility

Environmental record


See Also:

Railroads A-Z