Photo by File:Chicago River ferry.jpg : John Picken derivative work: Georgfotoart via Wikimedia Commons, CC BY 2.0
United States › Chicago › Races
Chicago Half Marathon
Half marathon, 5K in Chicago, normally held in September. A mixed half marathon course — Lakefront out-and-back on DuSable Lake Shore Drive.
The Chicago Half Marathon at a glance
| Distances | Half marathon, 5K |
|---|---|
| Main distance | 21.1 km (half marathon) |
| Usually held | September |
| Course | Mixed |
| City | Chicago, United States |
| Typical conditions | 23.9°C high / 16.3°C low, rain on ~33% of days |
Lakefront out-and-back on DuSable Lake Shore Drive.
Entering the Chicago Half Marathon
Entry fees, closing dates and start times are set by the organiser and change every year, so they are not reproduced here — a stale deadline is worse than none. The organiser’s own site and its social channels are the authoritative source for the current year, and are where entry opens.
What is stable, and what this page covers: the month the race is held, what the course is like, the conditions you should expect, and how long a build-up the distance needs.
Weather at previous Chicago Half Marathon races
Across the last ten years, Chicago in September has averaged a daily high of 23.9°C and a low of 16.3°C, with at least a millimetre of rain on about 33% of days.
These are recorded observations for the race month averaged over ten years, not a forecast and not a single past race day — race dates move, so one day’s figures would mislead. Source: Open-Meteo historical archive.
How to prepare for the Chicago Half Marathon
How long to train
Build for 12 to 14 weeks from a base you already hold rather than from nothing. For half marathon the block should peak at a longest run of 18–20 km, reached at least two weeks before race day so there is time to taper. Ten days of reduced volume is enough of a taper at this distance; keep one short session at race pace in the final week.
Training for this course
The course mixes surfaces and gradients, so build a training block that does the same rather than repeating one flat loop. Vary where you run week to week so nothing on race day is unfamiliar.
Conditions in September
Conditions are usually good for racing: highs average 23.9°C and lows 16.3°C in September, which is close to ideal for half marathon running. Dress for the temperature about ten degrees warmer than it actually is, since you will warm up within two kilometres.
Fuelling
A half marathon needs one gel or its equivalent around the hour mark for most runners, and a normal breakfast two to three hours before the start. Practise the same timing in at least three long runs so race morning is a repeat, not an experiment.
Race week
Sleep matters most two nights before, not the night before, so protect that one. Keep eating normally with a modest tilt toward carbohydrate, lay out kit the night before, and do nothing new: no new shoes, no new breakfast, no new socks. Plan to arrive at the start with time to spare — half marathon fields move slowly through bag drop and security.
Distances and where the race is run
- Half marathon — 21.1 km
- 5K — 5 km
The pin marks Chicago city centre, the area the Chicago Half Marathon starts and finishes in. This is not the course line: the route is set by the organiser and changes between editions, so the official course map for the current year is theirs to publish. The routes below are for training on the same roads.
Train on these roads: 10K routes in Chicago · long runs in Chicago · GPS art routes
Other races in Chicago
- Bank of America Chicago Marathon — Marathon, October
- Bank of America Shamrock Shuffle — 8K, March or April