The THC's successor inspired a reorganisation in 1964 that saw Hants & Dorset and northern neighbour Wilts & Dorset fall under common management, at Hants & Dorset’s head office in Bournemouth.

A year earlier, Wilts & Dorset had taken over a large independent, Silver Star of Porton Down.
As part of the THC’s early rationalisation, Wilts & Dorset had previously, in 1950, taken over the Basingstoke operator Venture, which had passed to the Red & White group five years earlier and which, following Red & White’s voluntary nationalisation, had in turn passed to the THC.

Upon both Hants & Dorset and Wilts & Dorset passing to the National Bus Company (NBC) on 1 January 1969, as a result of the Transport Act 1968, the operators merged in 1972 under the Hants & Dorset name and management.
Rather than Hants & Dorset's green, the enlarged operation adopted a fleet livery of National poppy red, similar to Wilts & Dorset's.
The new operation covered routes from Pewsey in the north, Poole to Fareham in the south, Basingstoke in the east, and Shaftesbury and Warminster in the west.

A year later, the substantial Winchester operator R Chisnell & Sons (t/a King Alfred) passed to Hants & Dorset, along with an eclectic mix of vehicles, most of which were withdrawn from service as non-standard.
Chisnell had operated Winchester city services and a country service to Basingstoke.

Hants & Dorset took over the services operated by Western National in Swanage in 1974.

Hants & Dorset had a reputation among NBC subsidiaries as somewhat loss-making.
While routes in the Poole-Bournemouth, Southampton, Basingstoke and Salisbury areas made reasonable returns, those elsewhere were weaker.
The impact of the private car throughout the 1960s and 1970s together with successive withdrawals and fares revisions further weakened what had now become marginal rural services.
During the 1980s, Hants & Dorset's financial position was so precarious that it had to be propped up by an inter-company loan from fellow NBC subsidiary Amalgamated Passenger Transport Ltd in order to remain solvent.
The THC's successor inspired a reorganisation in 1964 that saw Hants & Dorset and northern neighbour Wilts & Dorset fall under common management, at Hants & Dorset’s head office in Bournemouth.
A year earlier, Wilts & Dorset had taken over a large independent, Silver Star of Porton Down. As part of the THC’s early rationalisation, Wilts & Dorset had previously, in 1950, taken over the Basingstoke operator Venture, which had passed to the Red & White group five years earlier and which, following Red & White’s voluntary nationalisation, had in turn passed to the THC.
Upon both Hants & Dorset and Wilts & Dorset passing to the National Bus Company (NBC) on 1 January 1969, as a result of the Transport Act 1968, the operators merged in 1972 under the Hants & Dorset name and management. Rather than Hants & Dorset's green, the enlarged operation adopted a fleet livery of National poppy red, similar to Wilts & Dorset's. The new operation covered routes from Pewsey in the north, Poole to Fareham in the south, Basingstoke in the east, and Shaftesbury and Warminster in the west.
A year later, the substantial Winchester operator R Chisnell & Sons (t/a King Alfred) passed to Hants & Dorset, along with an eclectic mix of vehicles, most of which were withdrawn from service as non-standard. Chisnell had operated Winchester city services and a country service to Basingstoke.
Hants & Dorset took over the services operated by Western National in Swanage in 1974.
Hants & Dorset had a reputation among NBC subsidiaries as somewhat loss-making. While routes in the Poole-Bournemouth, Southampton, Basingstoke and Salisbury areas made reasonable returns, those elsewhere were weaker. The impact of the private car throughout the 1960s and 1970s together with successive withdrawals and fares revisions further weakened what had now become marginal rural services. During the 1980s, Hants & Dorset's financial position was so precarious that it had to be propped up by an inter-company loan from fellow NBC subsidiary Amalgamated Passenger Transport Ltd in order to remain solvent.
Hants & Dorset