Bern: The Swiss EU package cleared its first parliamentary hurdle on 1 October, when the Council of States finished a roughly 24-hour debate and sent most of the text to the National Council with amendments. The upper house also took a decision that could reshape the politics of the whole deal, because it asked for a mandatory referendum rather than the optional one the Federal Council proposed.

The difference is not procedural trivia. An optional referendum needs only a simple popular majority, while a mandatory vote requires a majority of voters and a majority of the cantons. Switzerland’s smallest and most rural cantons count for more under that rule, and they tend to be the most sceptical about closer ties with Brussels. The Swiss People’s Party, the largest party by vote share, already opposes the Swiss EU package, so the cantonal hurdle matters.

The agreements themselves were signed on 2 March 2026 by Commission President Ursula von der Leyen and Swiss President Guy Parmelin. Negotiations opened in March 2024 and closed that December. The package contains 18 agreements, protocols and declarations, and it replaces more than 100 interlocking treaties that have governed relations since the early 2000s. It extends the single market to electricity and food safety, adds a health agreement, and brings Switzerland into European research and education programmes.

Senators largely kept the wage-protection compromise that Bern negotiated with the EU and the social partners. They dropped the blanket security deposit for foreign posting firms, which could still be demanded from a company that has already broken the rules, and they backed stronger protection against dismissal. On immigration, the chamber supported a safeguard clause that Switzerland could invoke if arrivals from the EU cause serious economic or social problems, with an immigration levy as one possible tool.

Money is part of the Swiss EU package bargain too. The Council of States approved CHF 3.3 billion in commitment credits for future contributions to European cohesion, with payments running from 2030 to 2036. Of that sum, CHF 2 billion targets economic and social disparities and CHF 273.4 million goes to migration-related projects, with roughly CHF 1 billion as an additional one-off commitment.

The timetable now decides how much political risk the government carries. The National Council is expected to take up the file in the winter session, and the electricity agreement is not expected to reach the upper house until December. A nationwide vote before the autumn 2027 federal elections remains possible, but parliament would need to move quickly, and most commentators expect Swiss voters to decide during 2027.

Brussels also has work to do before the Swiss EU package can take effect. The European Parliament must give its consent and the Council must conclude the agreements. The institutional rules in the Swiss EU package are demanding, since Swiss law would track EU law in covered areas and an arbitral tribunal would have to ask the Court of Justice about points of Union law.

For Brussels, the lesson is that a signed treaty is not a ratified one. The Swiss EU package now depends on a referendum rule that parliament, not the government, is writing, and the choice between a simple and a double majority may prove as decisive as any clause in the text.