The KOF Swiss Economic Institute's economic barometer increased to 106.7 points in August from the revised 104.2 points in July, according to a Friday release.
Analysts expected 103 points for the month.
KOF said the level is now "noticeably above" its medium-term average following consecutive increases in the previous months. Positive developments were seen in the indicator bundles for manufacturing, other services and foreign demand, while that for private consumption was "slightly under pressure."