July is the worst month to cross and January is the best
By Alan Scott · Who makes this · Tijuana, Baja California ·
There are 32 minutes between the heaviest month of the year and the lightest. That's the same gap as between the best and worst day of the week — and almost nobody talks about it.
The numbers
Each month compared against its own year, so the season doesn't get confused with one year being worse than another.
| Month | Monthly average | vs. its year | Years it came out worse |
|---|---|---|---|
| December | 100 min | +13 | 3 of 3 |
| July | 98 min | +10 | 4 of 4 |
| September | 91 min | +7 | 2 of 3 |
| April | 92 min | +4 | 3 of 4 |
| August | 89 min | +2 | 2 of 3 |
| May | 89 min | +1 | 4 of 4 |
| June | 85 min | −2 | 1 of 4 |
| November | 77 min | −5 | 0 of 3 |
| March | 77 min | −7 | 1 of 4 |
| January | 69 min | −12 | 0 of 3 |
| October | 81 min | −13 | 1 of 3 |
| February | 73 min | −13 | 1 of 4 |
July is the most reliable finding we have
All four years we measured, July came out worse than its own year. Not one exception — and in 2026 it ran 26 minutes above.
Summer vacation, plus the week of July 4th, plus the fact that in July nobody has a school schedule to keep. The July line is a line of people who aren't in a hurry to be anywhere at 8 a.m.
And January is a gift
69 minutes on average against 100 in December. All three Januaries we measured came out better than their year. It's the month when everyone has already crossed, already spent, and is staying home.
January and February are the two months to do your business on the other side, if you get to choose.
While we're here: 2026 is running worse than the three years before it
| Year | Average |
|---|---|
| 2023 | 88 min |
| 2024 | 88 min |
| 2025 | 79 min ← the best of the four |
| 2026 | 94 min ← the worst |
2025 was the best year of the four, and 2026 jumped 15 minutes. We cover that in this separate article.
What this data does NOT tell you
It's not a forecast for tomorrow. A Tuesday in January can be terrible and a Sunday in July can be calm.
It doesn't tell you the hour. All full-day averages, again.
And months with three years carry less weight than months with four. Our data starts January 29, 2023, so January, August, September, October, November and December have three years and the rest have four. We're saying it because it changes how much you should trust each row, and that's your information, not ours.
A light month is not a good month. January averages 69 minutes. That's still more than an hour sitting in line.
You might also want:
- The worst days of the year are December 15–23
- The heaviest border days of the last three and a half years
- Friday is the best day to cross
Sources
Data: San Ysidro, General passenger vehicle lane, northbound. SANDAG, from U.S. Customs and Border Protection records. Period: January 29, 2023 to August 8, 2026 · 1,266 days. Method: each day is compared against the median of days with the same weekday across its own full year, which separates the season from the year's trend. Retrieved: August 11, 2026.
We are not affiliated with CBP or SANDAG.
CHART · build spec
Same chart as the Spanish version — see 6_CONTENIDO/articulos/05_julio_peor_mes_enero_mejor.md. 🔴 Do not re-derive the values.
Label translations only: months in calendar order, direct labels on July and January, and 🔴 the asterisk on months with 3 years instead of 4, with the footnote.