The Swiss government announced after a cabinet meeting that it had decided to move beyond UN sanctions adopted by the UN Security Council last June.
"The Federal Council (government) decided to raise the level of sanctions on Iran to the one applied by its principal trade partners," the economy ministry said in a statement.
The changes to the existing Iran sanctions decree would be implemented on Thursday, it added.
The new measures extend a ban on deliveries of dual-use goods, technology or software that can be used in weapons production, as well as on heavy weapons exports, and include new rules on financial services.
"Restrictions on exports as well as prohibitions on finance are also decreed for some goods used by the Iranian oil and gas industry," the statement said.
Other measures on financial services include a ban on insurance and reinsurance, reporting obligations on banking and transfers with Iran, as well as an extended sanctions list of people and companies. Switzerland adapted its sanctions regime to the one voted by the UN Security Council in June 2010 about two months later.
Since then mainly Western economies, led by the United States and Switzerland's biggest trading partner the European Union, have applied tougher measures.
Ministers feared that a slacker Swiss regime could be used to circumvent trade sanctions, the statement said.
Swiss trade with Iran reached 740 million Swiss francs in 2010, including 700 million in exports, according to official Swiss trade figures, mainly pharmaceutical products, machinery and agricultural produce.