Ningbo dialect native speakers generally understand Shanghainese, another dialect of Wu.
However, Shanghainese speakers do not always have full understanding of the Ningbo dialect.
In terms of inter-intelligibility between dialects within the Yong-Jiang subgroup, they can be more accurately described as 'accents' (腔) as these dialects are relatively uniform and almost identical to each other aside from pronunciation differences and some minor lexical differences.
Notes: The Middle Chinese [-ŋ] rimes are retained, while [-n] and [-m] are either retained or have disappeared in the Ningbo dialect.
Middle Chinese [-p -t -k] rimes have become glottal stops, [-ʔ].