The decision, in one paragraph
Every Chicagoan who has driven I-94 east toward the dunes has done the sum in their head. Here is the decision it leads to. Buy in Illinois and you pay an excise of 10%, 20% or 25% by product, 6.25% in state sales tax and, inside Chicago, 3% to Cook County and 3% to the city. Buy in Michigan and the register adds a flat 10% excise and 6% sales tax. But cannabis bought in Michigan may not lawfully be driven home to Illinois, and the nearest Michigan city where we read menus, Grand Rapids, is 125 miles from the Loop in a straight line. Michigan makes sense for what you will use in Michigan. For anything you plan to bring home, buy here.
That is a stance, and it comes from the law rather than from preference. Illinois's cannabis regulator says cannabis should not be taken across state lines. Federal law, as the Transportation Security Administration's own guidance puts it, still treats marijuana as illegal unless it is hemp at or under 0.3% THC or an FDA-approved product. A car that leaves a Michigan dispensary for Chicago crosses into Indiana and then into Illinois, and no state's legalization covers the trip between them.
The two tax stacks, layer by layer
The two systems were written by different hands, and it shows. Michigan legalized by ballot: the Michigan Regulation and Taxation of Marihuana Act is Initiated Law 1 of 2018, and its 10% retail excise is the voters' number, applied to every adult-use product alike. Michigan Treasury adds that the 6% sales tax is charged on the price including the excise, so the two together come to 16.6% of the shelf price at the register.
Illinois legalized by statute, in the Cannabis Regulation and Tax Act of 2019, and legislators tuned the excise to the product. The Illinois Department of Revenue applies 10% to cannabis at or under 35% adjusted THC, 25% above that line, and 20% to every cannabis-infused product whatever its strength; concentrates and vape oil are taxed on their own THC level, so one above 35% pays 25%. On top come the 6.25% state rate and any local cannabis taxes: in Chicago, 3% to Cook County and 3% to the city, the most a municipality may levy.
Both states also tax the product before it reaches the shelf. Illinois charges growers a 7% cultivation privilege tax on their first sale. Michigan went much further this year: since 1 January 2026 a 24% wholesale excise has applied to adult-use marijuana under the Comprehensive Road Funding Tax Act. It never appears on a receipt, and it is a tax the voters' 2018 initiative never contained.
| Layer | Chicago store | Suburban Cook County store | Michigan store |
|---|---|---|---|
| Retail excise | 10% at or under 35% adjusted THC; 25% above; 20% on infused products | 10% at or under 35% adjusted THC; 25% above; 20% on infused products | 10% on every adult-use product |
| State sales tax | 6.25%, plus local general-merchandise rates | 6.25%, plus local general-merchandise rates | 6%, charged on the price plus the excise |
| County cannabis tax | Cook County 3% | Cook County 3% | None listed by Michigan Treasury |
| City or village cannabis tax | Chicago 3% | Up to 3%, set by each village | None listed by Michigan Treasury |
| Tax paid before the shelf | 7% cultivation privilege tax on the grower's first sale | 7% cultivation privilege tax on the grower's first sale | 24% wholesale excise since 1 January 2026 |
The drive, and the stores we do not read
The Michigan stores on our roster nearest to Chicago sit just over the line, in the Berrien County towns of New Buffalo, Niles and Buchanan. They are on our roster and not on our nightly list, so we have no prices for them and will not pretend otherwise. The nearest Michigan city where we read menus every night is Grand Rapids, 125 miles from the Loop as the crow flies and further by road, and an hour later on the clock, because Michigan runs on Eastern time.
Michigan's limits are generous by Illinois standards: an adult aged 21 or over may possess 2.5 ounces, no more than 15 grams of it concentrate, and a retailer may not sell more than 2.5 ounces in one transaction. None of that travels. The limit that applies to you on the drive home is the Illinois limit, and it assumes cannabis bought in Illinois.
What we would do from Chicago
Shop at home, and shop the tax line rather than the state line. A Chicago purchase carries 6 points of local cannabis tax, 3 to Cook and 3 to the city. A store in Oak Park or Berwyn sheds the city's 3 and may add a village rate of up to 3; a store in Kane County sheds Cook's as well. Those are the levers within reach of a train ride, and the five suburban stores we read are listed with their tax layers in our suburbs guide.
If you are in Michigan anyway, for a weekend on the lakeshore or a game in Ann Arbor, buy there, use it there, and leave with nothing. We read 23 Illinois stores every morning around 8 AM CT; the deals on this page come from their menus.