Due to the proximity of Brighton station to the Portland Building, a walk of around 6 minutes, rail is a very convenient way of commuting to the site from outside the Brighton and Hove area. Rail provides connections with centers along the South Coast and north along the route to / from London.
| Origin / Destination | Route Summary | Typical Hourly Frequency | Train Operator |
| Brighton / Eastbourne | Brighton – Moulsecoomb – Lewes – Glynde – Berwick – Eastbourne | 1 | Southern Rail |
| Brighton / Ore | Brighton – Lewes – Eastbourne – Bexhill – St Leonard’s – Hastings – Ore | 1 | |
| Brighton / Portsmouth & Southsea | Brighton – Shoreham – Worthing – Barnham – Chichester – Havant – Fratton – Portsmouth & Southsea | 1 | |
| Brighton / Southampton Central | Brighton – Shoreham – Worthing – Barnham – Chichester – Havant – Fareham – Southampton Central | 2 | |
| Brighton / Chichester | Brighton – Hove – Portslade – Southwick – Shoreham – Worthing – Littlehampton – Ford – Chichester | 1 | |
| Brighton / Seaford | Brighton – Lewes – Newhaven Town – (Newhaven Harbour) – Seaford | 2 | |
| Brighton / London Victoria | Brighton – Haywards Heath – Gatwick Airport – London Victoria | 2 | Gatwick Express |
| Brighton / Bedford | Brighton – Gatwick Airport – London Bridge – Blackfriars – St Pancras – Luton Airport – Luton – Bedford | 2 | Thameslink |
| Brighton / Cambridge | Brighton – Gatwick Airport – London Bridge – St Pancras – Finsbury Park – Stevenage – Hitchin – Cambridge | 2 | |