A closely contested referendum on resuming EU accession negotiations, scheduled for 29 August 2026, has produced tight market pricing across turnout buckets from 45-50% to 60-65% because of uncertainty over mobilization in a polarized campaign centered on fisheries sovereignty, economic stability, and geopolitical pressures. Recent polls show the yes side holding a narrowing 2-3 point edge, sustaining intense last-minute efforts by both camps that typically boost participation, while early voting from late July and historical referendum patterns—ranging from under 50% to over 75%—add variability. End-of-summer timing and the advisory nature of the vote, which would trigger negotiations but require a second referendum on any deal, further complicate projections of engagement levels among Iceland's roughly 267,000 registered voters.