The B561 was a short B-road to the west of Bedford.
It started on the B557 in Kempston and headed west through town. It went round the outside of a meander of the River Great Ouse to pass through Kempston Church End before heading north to its terminus on the A428 in Bromham.
Except for the easternmost section, the entire B561 was renumbered B562 in 1935. This was then upgraded to Class I status in the 1960s, becoming the A5134. It was downgraded again in 2009 following the construction of the A418 Bedford western bypass, which was built on a similar alignment. The easternmost section of the ex-B561 (which never became A5134) is now part of the B531. The section west to Kempston Church End is now B560 and the remainder unclassified.