The Swiss pine is a member of the white pine group, Pinus subgenus Strobus, and like all members of that group, the leaves ('needles') are in fascicles (bundles) of five, with a deciduous sheath. The mature size is typically between 25 metres (82 ft) and 35 metres (115 ft) in height, and the trunk diameter can be up to 1.5 metres (4.9 ft). However, it grows very slowly and it may take 30 years for the tree to reach 1.3 metres (4.3 ft). The cones, which contain the seeds (or nuts), of the Swiss pine are 4 centimetres (1.6 in) to 8 centimetres (3.1 in) long. Cones take 2 years (24 months) to mature. The 8 millimetres (0.31 in) to 12 millimetres (0.47 in) long seeds have only a vestigial wing and are dispersed by spotted nutcrackers. The species is long-lasting and can reach an age between 500 and 1000 years.

In its natural environment, this tree usually reaches reproductive maturity at the age of 50 years (even 80 years, if the conditions are more extreme).

The very similar Siberian pine (Pinus sibirica) is treated as a variety or subspecies of Swiss pine by some botanists. The Siberian pine differs in having slightly larger cones, being more massive (taller, wider trunk), having a faster growth rate and needles with three resin canals instead of two as in the Swiss pine.