The rare and atmospheric pairing of two National Coal Board locomotives will take place at the heritage railway's Autumn Steam Gala.
The gala will take place from September 18 to September 21 .
The railway has confirmed that NCB No 49 will appear at the event, giving the opportunity to run a historic double-header with GWR Port Talbot Tank No 813, in the guise of NCB No 11 on the Sunday of the event.
Jonathan 'Gus' Dunster, managing director at the SVR, said: "The return of 813 in its Backworth guise at No 11, alongside the visiting No 49, will be a very special moment for our Autumn Gala.
"It will be a rare opportunity to see two NCB locomotives from the same depot working together again, and we're grateful to the Tanfield Railway for helping to make this possible."
Returning to traffic, GWR Port Talbot Tank No 813 will run in a temporary livery as No 11, complete with authentic NCB detailing, its signature brass safety valve bonnet and cabside numbers removed.
This will be a short-lived appearance as the locomotive will be repainted in traditional GWR livery in due course.
This exciting NCB pairing joins a stellar line-up of locomotives for what promises to be one of the most ambitious Autumn Steam Galas in SVR history, including some first-time visitors to the line.
Among the headline guests are Merchant Navy 35006 'Peninsular and Oriental S N Co', and BR Standard Class 5 73082 'Camelot', which have never run previously at the SVR. The appearance of 35006 is particularly important, as it represents the first time any Merchant Navy locomotive has been seen at the heritage line.
These visiting engines will operate alongside an impressive home fleet, including 4930 'Hagley Hall', 7714, 7802 'Bradley Manor', 13268, 75069 and 1450 operating as an Autotrain.
In a special move to mark 60 years since the SVR was founded, the line will be in continuous operation for 60 hours, from early Friday morning through to Sunday evening, with overnight running on both Friday and Saturday - offering unmatched opportunities for atmospheric night-time steam photography and travel.
Advance tickets are available now with up to 10 per cent discount, and great-value multi-day rover tickets allow visitors to experience all highlights of the four-day event.
For tickets and full event details visit www.svr.co.uk