From 1896 he worked as a decorative painter, after 1900 as an artist with his own art publishing house in Cologne. His time in the Netherlands from 1901, his father's country of origin, was accompanied by several changes of location: 

1901-1905 Keulen and Zaandam, 1905-1907 Edam, 1907-5 April 1910 Leiden. In the Netherlands.

Paul Matthes was a member of the artists' association "Arti et Amicitiae" (Art and Friendship – Association for the Promotion of Fine Arts) based in Amsterdam. 

As early as 1907, the artist registered another residence in Lucerne/Switzerland, Vonmattstraße 52. 

With his wife Minni Schihel and his three children, he moved from there in 1912 to Zürichstraße 79. Also in Lucerne, the artist ran his own publishing house.

During the First World War, Paul Matthes was forced to land storm without a weapon in Königsberg, but was deferred by the army for health reasons. 

On 14 November 1918, he travelled back to Switzerland. In 1919 Paul Matthes separated from his family and settled in Potsdam. Here he used social relations with the members of the "Potsdamer Kunstverein of 1909" and the "Potsdamer Kanu-Gesellschaft e. V." 

In the 1920s, the painter acquired a sailboat, later a houseboat, which became the preferred place to stay during the summer months on the lakes of Brandenburg and Mecklenburg. After 1945, Edith Bender, an art gewerbler from Elbing/East Prussia, who he married in 1952, accompanied him on his boat tours. 

In 1946, the painter was recognised as a freelance artist and became a member of the Schutzverband bildener künstler on 22 January 1947. From 1948 he lived in Bergholz-Rehbrücke, until 1952 a district of Potsdam, Feldstraße 67 and 92 respectively. He died there on 16 March 1956 and was buried in the cemetery in Bergholz.

Paul Matthes was self-taught. Graphics dominate the overall work. For his event pictures and city views, he used both the technique of lithography and copperplate engraving. The art postcards he designed with city and landscape views from the Netherlands, Switzerland and Germany have high motif numbers, which are coveted collector's items today. His artistic development can be seen particularly in the different techniques of oil painting, some of which have only recently been identified and thus compared. In this, the artist proves himself to be a naturalist in general - but until 1920 he was strongly influenced by the painting style of the Impressionists with lighter colours.