The following sorting codes have been used in preparing the database to enable otherwise coherent groups of papers which are now dispersed through the archive to be brought together:
| AICOR | African Institution: correspondence |
| AIP | African Institution: papers |
| BATH | Papers from Lord Bathurst's archive (Cirencester Park) |
| BLHCOR | British Lying-in Hospital for Married Women (also called The Lying In Charity, established 1757: Wellington president in 1819 and later): correspondence |
| BLHP | British Lying-in Hospital for Married Women: papers |
| BUNLAB | Bundle label |
| BWES | Bath and West of England society for the encouragement of arts and agriculture: Wellington was Vice Patron in 1830 and for several years before (WP1/1129/7) |
| CALACOR | Caledonian Asylum correspondence |
| CALAP | Caledonian Asylum papers |
| CHGOVCOR & P | Correspondence and papers as Governor of the Charterhouse, from 9 August 1828 |
| CHOXCOR | Correspondence and papers as Chancellor of Oxford University (1834-52) |
| CICCOR & P | Correspondence and papers as Commander in Chief of the army |
| CORCOP | Copy of correspondence made in preparation for editions of the Dispatches, in an unidentified hand |
| CSICOR & P | Correspondence and papers as Chief Secretary for Ireland (1807-9) |
| CTLCOR | Constable of the Tower of London: correspondence |
| CTLP | Constable of the Tower of London: papers |
| DESP | Proofs etc. for the editions of the Dispatches |
| DPFCOR | Trustee of the Deccan prize fund (appointed 23 March 1823: WP1/766/10): correspondence |
| DPFP | Trustee of the Deccan prize fund: papers |
| ELDCOP | Copies taken from the papers of the first Earl of Eldon after his death in 1838 and in the 1840s (mainly Eldon, Goderich, Westmorland and King George IV) |
| ELPS | East London Pension Society. Duke of Wellington patron from 1828 (WP1/986/5) |
| FGCOR | Correspondence of William Fitzgerald, later second Baron Fitzgerald and Vesey, given to the second Duke of Wellington in 1871. |
| FSRCOR & P | As colonel of the 42nd Regiment of the Line of the Austrian army |
| GENCOR | General correspondence |
| GENP | General papers |
| GEXCOR & P | As George IV's executor |
| GOVPLYCOR | Governor of Plymouth (Wellington resigned on appointment to the Tower of London, 29 December 1826): correspondence |
| GOVPLYP | Governor of Plymouth: papers |
| GRENCOR & P | Colonel of the Grenadier Guards (22 January 1827-1852) |
| GURCOP | Copy by Colonel J.Gurwood (see also JGP) |
| HCT | Harcourt papers |
| HLCOR | Hampshire Lieutenancy correspondence |
| HLP | Hampshire Lieutenancy papers |
| HSLCOR & P | Highland Society of London (Wellington was an honorary member in 1829) |
| JCHP | Papers of Sir John Cox Hippisley, 1st Baronet |
| JGP | Papers from Gurwood's possession |
| KCLCOR | As a life governor of Kings College, London (from August 1829) |
| LHCOR & P | London Hospital: Wellington Vice President in 1819 |
| LVICOR | London Vaccine Institution: Vice President of the board of managers |
| LWCPCOR | Lord Warden of the Cinque Ports and Constable of Dover Castle |
| MAP | Maps and plans |
| MBSCOR | Medico-Botanical Society: honorary fellow 16 March 1827 (WP1/885/14) |
| MGOCOR | Master General of the Ordnance: correspondence |
| MGOP | Master General of the Ordnance: papers |
| MILCOR | Military correspondence |
| MILP | Military papers |
| MRTCOP | Copy by R.M.Martin |
| MRTOR | Original document removed from another archive by R.M.Martin |
| MSCOR | Military secretary's correspondence |
| MSP | Military secretary's papers |
| MXHCOR | Middlesex Hospital correspondence (Vice President 1819) |
| MXHP | Middlesex Hospital papers |
| POLCOR | Political correspondence |
| POLP | Political papers |
| PRICOR | Private correspondence |
| PRIP | Private papers |
| RFLBCOR | Rifle Brigade correspondence (1820-52) |
| RFLBP | Rifle Brigade papers |
| ROYCOR | Royal correspondence |
| ROYP | Royal papers |
| RRHGCOR | Royal Regiment of Horse Guards (and Gold Stick) correspondence (1813-27) |
| RRHGP | Royal Regiment of Horse Guards papers |
| RWHCOR & P | Royal Western Hospital (part later Royal York Hospital) |
| RWICOR | Royal Westminster Infirmary for Diseases of the Eye (Wellington was President from at least 1823): correspondence |
| RWIP | Royal Westminster Infirmary for Diseases of the Eye: papers |
| SABCOR & P | Society of Arts in Birmingham: Wellington patron from April 1829 (WP1/1011/26) |
| SFFDCOR | Society of Friends of Foreigners in Distress (Wellington was President in 1819 and later): correspondence |
| SFFDP | Society of Friends of Foreigners in Distress: papers |
| SPBSCOR | Benevolent Society of St. Patrick: correspondence |
| SPBSP | Benevolent Society of St. Patrick: papers |
| SSCOR | Shakespeare Society correspondence |
| SSP | Shakespeare Society papers |
| SSPCKHICOR & P | Society in Scotland for propagating Christian knowledge in the Highlands and Islands: Wellington was Vice President in 1819 (WP1/623/18) |
| THOCOR | Trinity House correspondence: Elder Brother, April 1829; Master, May 1837 |
| TRCOR & P | Correspondence with the Duke's trustees, etc. under 54 George III, cap. 161 |
| TTFCOR & P | Colonel of the Thirty Third Regiment of Foot (1806-12) |
| VECOR & P | Correspondence as plenipotentiary to the congress of Verona, transferred from Vienna |
| WICOR | Commissioner for the Improvement of Windsor Castle (Wellington appointed 1824): correspondence |
| WIP | Commissioner for the improvement of Windsor Castle: papers |