Public transport services have been provided in the Province of Como since 1906, when Società Tram Elettrici Comensi (STEC) launched Como's first tram line between San Giovanni FS railway station and the Brunate funicular railway station.
In 1908, Società Elettrica Comense Alessandro Volta (SECAV), a company already providing a range of public services, acquired STEC and took over the tram services, which had expanded to cover the Ponte Chiasso and Trecallo areas. Within a few years, the tram system had extended beyond the city limits, servicing Maslianico, Ponte Chiasso, Cantù-Asnago FS, Mozzate and Lecco, as well as the Viale Varese - San Rocco and San Martino urban routes.
In 1934, STECAV embarked on the first phase of transforming its services by replacing the tram routes between Cantù-Centro and Cantù-Asnago FS and between Appiano Gentile and Mozzate with bus services.
In 1938, it began running trolleybuses on the Como-Maslianico and Como-Ponte Chiasso routes.
The new Como-Camerlata trolleybus service began operating in 1947.
By 1955, all remaining tram routes were replaced by trolleybus services (Cantù) or motorbus services (Appiano Gentile and Lecco).
In 1956, the trolleybus network reached peak expansion with 28 km of overhead lines.
In the 1960s, STECAV, the sole operator serving urban areas in the Municipality of Como (with the exception of the Civiglio route, operated by SALVI) expanded its public services, beginning to replace the San Martino urban trolleybus service with a circle line motorbus service in 1964.
July 1971 saw implementation of a plan to significantly increase urban public transport services by introducing "Giallo Bus" [Yellow Bus], a mixed trolleybus/motorbus service operating between Breccia/Albate and Ponte Chiasso, i.e. the "spine" route.
In April 1974, the newly incorporated Azienda Comasca Trasporti (ACT), owned by the Municipality of Como, took over all urban services previously provided by SALVI and STECAV and, on 1 April 1974, began operating 6 bus routes across the urban area. The former operators continued to provide non-urban services, managing the Como-Maslianico and Como-Cantù trolleybus routes, the Appiano Gentile and Lecco motorbus services and a number of other short non-urban connections.
In 1977, ACPT (Azienda Consortile Pubblici Trasporti) was established in the province of Como as a consortium management company to handle transport services no longer provided by STECAV and SALVI, which had gone bankrupt. ACPT began operating on 25 September 1977, acquiring all routes previously serviced by SALVI from ACT Como – the urban operator that had been running them on a temporary basis for a year – and all STECAV routes, including the Como-Cantù trolleybus service. The latter continued to run for a few months, before being replaced by motorbuses in June 1978, marking the end of the trolleybus service in Como. The newer vehicles were acquired by ACPT; while only the Alfa Romeo 140AF and Fiat 668 trolleybuses remained in service until the Como-Cantù route was discontinued.
1989 saw the merger of the two public transport service companies (A.C.T and A.C.P.T.) and the incorporation of SOCIETA PUBBLICA TRASPORTI (S.P.T.) spa on 23 February of that year. The company was owned by the Province and the Municipality of Como and Consorzio Pronvinciale Trasporti Pubblici, with share capital of 300 million. The Province of Lecco became a shareholder in 1998, shortly after its establishment.
The company began operating on 1 June 1991, taking over the routes and vehicles previously managed by ACPT and CT.
The Peroni d’Erba business was also acquired in 1999.
Regional Law 22/1998, later supplemented by Regional Law 1/2002, introduced new requirements for public transport companies. In accordance with this regulation, and in order to be able to tender for transport routes, a new public transport management company was established on 27 February 2002.
SPT Linea S.r.l. was founded on 1 January 2003 to manage the public transport service, with SPT retaining ownership of real estate property and depots and continuing to handle rental services and tourist routes.
On 1 July 2005, a temporary association of companies consisting of SPT LINEA srl and ATM S.p.A. took over the running of local public transport services for the Municipality of Como and its urban area, having been awarded the tender.
SPT LINEA srl handled the bus services (12 routes), while ATM operated the Como – Brunate funicular railway service.
On 9 June 2006 the temporary association of companies became Co.Mo. Fun&Bus Scarl, handling the service contract in association with the Municipality of Como.
Another tender saw the public transport service contract for the Province of Como being awarded to a temporary association of companies made up of SPT LINEA srl, FNMA and AGI.
By 1 July 2005, SPT LINEA srl was providing approximately 84% of non-urban services for the Province of Como, with the remaining 16% provided by FNMA.
On 26 October 2005, a limited liability consortium was established under the name STECAV S.c.a.r.l. “Società Trasporti Extraurbani Consortili Alessandro Volta”, handling the service contract in association with the Province of Como.
SPT LINEA provides a small portion of the service in the Province and Municipal Districts of Lecco, totalling approximately 8%. The temporary association of companies awarded the service contract for that area founded LECCO TRASPORTI S.c.a r.l. to manage dealings with the awarding authority.
As well as the services referred to above, SPT LINEA continues to operate two international routes: Como - (Ponte Chiasso) - Chiasso and Porlezza - Lugano.
On 11 September 2007, 49% of the company capital of SPT Linea was acquired by Omnibus Partecipazioni, a company owned by ARRIVA ITALIA and FERROVIE NORD Spa, and the company changed its name from SPT Linea to ASF Autolinee S.r.l.. 51% of the company capital is held by SPT spa.
Company capital currently stands at € 7,460,785.00.