City comparison
Longmont, CO is about 20 miles (30 km) from Thornton, CO in a straight line. By road, the drive is roughly 20 miles, or about 24 min behind the wheel at highway speeds.
Driving distance is a rough estimate (great-circle × 1.25); driving time assumes a 60 mph blended average. Real trips run 10–20% longer with stops.
A direct flight from Longmont, CO to Thornton, CO takes about 2 min, covering roughly 20 miles in a straight line. Connecting itineraries with a layover typically add 1–3 hours.
Block-to-block estimate at ~500 mph cruise, including taxi, climb, and descent — what an airline would publish, not pure airborne time.
Thornton has a population of 141,799, vs 98,282 in Longmont — about 1.4× larger by population. By land area, Thornton covers about 37 sq mi vs 29 sq mi for Longmont.
Population from US Census ACS. Land area from the Census Gazetteer (city proper, excluding inland water).
Cost indices by category, with the US city average (100) marked.
Index: 100 = US city average. Lower is more affordable.
Side-by-side costs, salaries, and sub-category indices.
| Metric | Longmont | Thornton | Difference |
|---|---|---|---|
| Median rent | $1,689/mo | $1,758/mo | 4.1% higher in Thornton |
| Median home value | $488,100 | $445,200 | 9.6% higher in Longmont |
| Median household income | $89,720 | $95,064 | 6.0% higher in Thornton |
| Groceries index | 96.8 | 101.2 | 4.6% higher in Thornton |
| Utilities index | 86.5 | 91.2 | 5.4% higher in Thornton |
| Transportation index | 100.3 | 99.9 | ≈ equal (Longmont slightly higher) |
| Healthcare index | 100.2 | 99.9 | ≈ equal (Longmont slightly higher) |
How much you'd need to earn in the other city to keep the same standard of living.
If you earn $100,000 in Longmont, you'd need $97,836 in Thornton to maintain your standard of living.
Climate, safety, and demographics side by side.
Thornton, CO is about 2.2% cheaper overall than Longmont, CO, based on our cost-of-living index. Housing costs are roughly 6% higher in Longmont than in Thornton. If you earn $80,000 in Longmont, you'd need about $78,269 in Thornton to keep the same standard of living.