^Columbine was built as number 49 of the Grand Junction Railway but is preserved in later guise as number 1868 of the London and North Western Railway.
^Cornwall was originally numbered 173 but is preserved with its later number 3020.
^North Eastern Railway 66 was later renumbered 1478.
^The Beattie Well tank was built by Beyer Peacock in 1874 for the London and South Western Railway. It initially carried the number 298 but this was later changed to 0298 in a duplicate series and was rebuilt at their Eastleigh Works in 1921. When it became the property of the Southern Railway it initially carried the number E0298 but this was changed to 3298. It is preserved in British Railways guise with its final number 30587.
^Boxhill was originally numbered 82 but this was later changed to 682. On transfer to the Southern railway this became 380S in their Service Stock series.
^Gladstone was originally numbered 214 but was renumbered 618. Upon transfer to the Southern Railway this became B618.
^Lancashire and Yorkshire Railway 1008 was numbered 10621 by the London Midland and Scottish Railway, and 50621 by British Railways.
^Hardwicke was London North Western Railway 790 and then London Midland and Scottish Railway 5031.
^Only the tender of Stirling Single 1002 survives. It has been attached to Single No. 1 since 2014.
^T26 Class 490 was built for the Great Eastern Railway. The London and North Eastern Railway gave it the number 7490 in 1923 but later changed this to 2785, so for British Railways it was number 62785.
^M7 Class 245 was numbered E245 by the Southern Railway but later reverted to plain 245; under British Railways ownership it carried number 30245.
^Taff Vale Railway number 28 became 450 in Great Western Railway ownership.
^Henry Oakley was renumbered 3990 by the London and North Eastern Railway.
^Midland Railway 673 had earlier carried number 118.
^Great Northern Railway 1247 became 4247 under London and North Eastern Railway ownership. This was later changed to 8846 so it became British Railway's 68846.
^T9 number 120 became Southern Railway's E120 before reverting to 120. For British Railways it was renumbered 30120.
^South Eastern and Chatham Railway 737 became Southern Railway A737 before renumbering to 1737. Under British Railways it was number 31737.
^Midland Railway 1000 was originally numbered 2361. Under British Railways it was number 41000.
^Great Eastern Railway 877 became London and North Eastern Railway 7087 before renumbering to 8633. Under British Railways it was number 68633.
^Great Eastern Railway 1217 became London and North Eastern Railway 8217 before renumbering to 5567. Under British Railways it was number 65567.
^80 Thundersley became Midland Railway 2177. It retained this number with the London Midland and Scottish Railway but was later renumbered to 2148. Under British Railways it was number 41966.
^63601 was originally Great Central Railway 102. It became London and North Eastern Railway 5102 before renumbering to 3509.
^North Eastern Railway 901 retained its number with the London and North Eastern Railway for many years but was eventually renumbered as 3460. Under British Railways it was number 63460.
^Butler Henderson became London and North Eastern Railway 5506 before being renumbered as 2660. Under British Railways it was number 62660.
^49395 was originally London and North Western Railway 485, later Midland Railway 9395.
^Flying Scotsman was originally numbered 4472 but later carried the numbers 502 then 103. British Railways numbered it 60103.
^Green Arrow was originally numbered 4771 but later carried number 800 before becoming British Railways' 60800.
^Mallard was originally number 4468 but was renumbered as 22 before becoming British Railways' 60022.
^Duchess of Hamilton was numbered 46229 by British Railways.
^The Q1 Class 0-6-0 carried the number C1 when built but was numbered 33001 by British Railways.
^Sir Winston Churchill was numbered 21C151 by the Southern Railway and 34051 by British Railways.
^Ellerman Lines was built by British Railways to an earlier Southern Railway design. It has been sectioned to show its construction.
^The Barclay fireless locomotive was owned by Imperial Paper Mills.
^Frank Galbraith was owned by the Teesside Bridge & Engineering Co.
^The South African Railways Class 7A carries its SAR number 993, but when built for the Cape Government Railways it was numbered 390.
^The South Devon Railway was absorbed by the Great Western Railway in 1876 and Tiny was then allocated number 2180.
^The North Star replica includes some parts from 1837 original.
^Iron Duke is a replica of a GWR locomotive built in 1847.
^Southern Railway 75S was numbered DS75 by British railways.
^North Eastern Railway electric locomotive number 1 was renumbered 4075 and then 6480 by the London and North Eastern railway. Under British Railways numbering it carried 26500.
^North Staffordshire Railway battery electric locomotive no. 1 later carried British Railways number BEL2.
^The CEGB Bolton battery electric locomotive originally entered service with the South Wales Electrical Power Distribution Co. at Upper Boat power station, where it was registered as no. 258 to work on the Great Western Railway.
^Locomotive E26020 later carried the TOPS number 76020.
^Locomotive 1505 originally carried the number 27001, prior to its sale to Nederlandse Spoorwegen in 1969
^Locomotive E5001 later carried the TOPS number 71001.
^Locomotive 84001 originally carried the number E3036.
^Class 47 locomotive number D1656 became 47072 in 1974 after the TOPS numbering system came into use. Its steam heating boiler was replaced by electric train heating in 1984 and therefore renumbered 47609. The following year it was given the name Fire Fly to commemorate an historic Great Western Railway steam locomotive and was further renmubered to 47834 in 1989. In 1995 it was renumbered once more to 47798 and the name changed to Prince William; it was also repainted in plum colour as one of the locomotives allocated to pull the British Royal Train.
^41001 was one of the two power cars of the prototype High Speed Diesel Train which, as a complete train, carried the number 252001. It carried car number 43000 and later ADB975812 when no longer in revenue service.
^The Class 41 was the prototype for the InterCity 125 or "High Speed Train".
^Simplex 2275 worked at Knostrop Sewage Works but was originally built for the War Department Light Railways.
^Ruston Hornsby 187105 was used by the Yorkshire water Authority at Naburn Sewage Works.
^Number 14 was operated by the National Coal Board at Ellington Colliery, Northumberland.
^Number 9 was operated by the National Coal Board at Ellington Colliery, Northumberland.
^London and South Western Railway 563 was numbered E563 by the Southern Railway before reverting to 563, and 30563 by British Railways.
^London and South Western Railway 563 was donated from the National Collection to the Swanage Railway in 2017.
^Great Western Railway 2818 was donated from the National Collection to STEAM – Museum of the Great Western Railway in 2017.
^North Staffordshire Railway number 2 was later London Midland and Scottish Railway number 2271. It was then sold to Manchester Collieries where it was their number 2.
^North Staffordshire Railway number 2 was transferred from the National Collection to the Foxfield railway in 2016.
^RSH 0-4-0ST Eustace Forth was donated from the National Collection to the Foxfield Railway in August 2014.
^0-6-0ST King Feisal of Iraq is currently at the Flour Mills Workshops in Bream, Gloucestershire for overhaul.
^Ownership of Austerity tank King Faisal of Iraq was transferred from the National Collection to the Flour Mill in February 2016.
^Handyman was donated from the National Collection to the Statfold Narrow Gauge Museum Trust in 2021.
^Ownership transferred from NRM to Friends of the 502 group by October 2011.
^Ownership of 4-VEP 3545 was transferred to the East Kent Railway as of 2016.
^Ownership transferred from NRM to Crewe Heritage Centre Trust by April 2018
^De-accessioned from the National Collection in 2022.
^Into National Collection in 1977, de-accessioned around 2015.
^10825 joined the National Collection through the Science and Industry Museum collection. The carriage was de-accessioned and transferred to the LMS Carriage Association in 2018.
^At Ropley for major restoration on 25-year loan since 2012.
^During re-appraisal of items from the National Collection in the 1990s, 1456 went to the Bluebell.
^311 Eagle was part of the National Collection but was reported to be no longer be part of it in February 2019.
^13252 was said to no longer be a part of the National Collection on its RHRP (VCT carriage survey) page and now owned by the Mid-Norfolk Railway.
^Ownership transferred from NRM to the Nene Valley Railway in April 2005.
^Donated to the Nene Valley Railway by the NRM in March 1996.
^Body of the van scrapped in September 2011. Donated by NRM to Aysgarth Station Project.
