What we do not know yet
The short answer
The vote on 29 August is about whether to open negotiations. Many of the most important questions therefore cannot be answered until a deal is on the table. The main uncertainties are gathered here — grouped by topic, each linked to the data and sources behind it.
What would membership cost — and what would come back?
- The net position (the ISK 10–20bn estimate) is extrapolated from Denmark/Finland — not a negotiated outcome.
- The Commission stopped publishing official net balances after 2020; figures here are computed from its spending and revenue data.
- The 2028–2034 EU budget framework is not yet agreed — the rules Iceland would join under are still being written.
The euro: benefits, costs — and when could it arrive?
- When Iceland would meet the Maastricht criteria. Inflation is 5.3% today and the benchmark moves with whichever members are performing best — whether and when the gap closes is a forecast, not a fact.
- How long ERM II would last. Two years is a minimum, not a maximum, and the exit date is not set in advance.
- Whether — and by how much — mortgage rates for households would fall. Euro-area policy rates are not the same thing as the rates Icelandic banks charge: margins, competition and the housing market matter too.
Government debt: Iceland in European comparison
- The latest years in the IMF series are estimates subject to revision; Iceland’s 2025 figure (~56%) is an estimate, not final accounts.
- The IMF definition is not the Maastricht definition — a formal convergence assessment uses EDP figures Iceland does not currently report to Eurostat.
How much influence would Iceland have in the EU?
- What would actually be negotiated. Seats, a Commissioner and any derogations are matters for negotiation — the figures here are derived from the rules as they stand, not from an accession treaty that exists.
- How much Iceland would actually get its way. Formal vote weight is measurable; how small states build coalitions and what they extract in Council negotiations is not.
- What share of the legislation Iceland already adopts under the EEA would fall under its vote inside the EU. The comparison with the status quo is not a single clean number.
What changes for fisheries?
- The fisheries chapter was never opened in 2010–2013 — all claims about “what the EU would have offered” are speculation, in both directions.
- How fishing fees, quota ceilings and transfer rules in Icelandic law would interact with EU rules is unresolved.
- The precise ownership impact depends on negotiated “genuine economic link” conditions tying vessels to Iceland.
What happens to farming?
- The ~11% Finnish price drop is a research finding, not an official statistic — and 1995 conditions differ from 2026.
- Finnish farm numbers also fell in non-member Norway — the trend is partly independent of membership.
- Which land counts as eligible (cultivated vs. rough grazing) and the size of nordic aid are pure negotiation outcomes.