Canada
Work 1 year on work permit → PR eligible (some programs) → 3 years PR → citizenship. Total: 4 years.
USA
Work visa (H1B) 3+ years → Green Card 5+ years → citizenship eligible. Total: 8+ years.
Australia
Temporary skilled visa 2 years → PR (if eligible) → 4 years PR → citizenship. Total: 6+ years.
UK
Work visa 5 years → ILR application → ILR granted → 12 months → citizenship eligible. Total: 6+ years.