Illinois Sales Tax Nexus Rules Updated for 2026

The Illinois Department of Revenue (DOR) has updated its sales and use tax guidance on how out-of-state retailers and service providers should determine whether they have a physical presence in Illinois and, if so, must collect and remit the appropriate taxes on sales made to customers in the state. In addition to clarifying key rules, the updated guidance provides numerous real-life scenarios as examples.

Key Updates from the Tax Guidance

The first notable change is the expansion of the definition of “sale” to include not only traditional retail transactions, leases, or rentals of tangible personal property, but also situations in which tangible goods are transferred to a customer as part of a service transaction. Additionally, it clarifies that the term seller includes both retailers and service providers.

The key question for both retailers and service providers is whether they have a physical presence in Illinois or meet the USD 100,000 economic nexus threshold. The threshold is established specifically for remote sellers and service providers, including marketplace facilitators, who have no physical presence in the state but still sell enough to local customers to trigger collection obligations.

In addition to explaining the differences between in-state tax rules and those for remote sellers, the updated guidance also provides new examples and charts to help businesses determine how a sale should be sourced and whether their activities create a physical presence in the state. 

Regarding the sourcing, the DOR noted that determining where each sale is made must be done on a sale-by-sale or transaction-by-transaction basis rather than as a blanket determination. The DOR added that the key distinction is whether the sale originates in or out of Illinois, which then determines whether origin- or destination-based tax rates apply.

Conclusion

The updated guidance on sales and use tax from a nexus perspective is a valuable resource for both in-state and remote sellers. Given the broader definition of the term sale, businesses that have not recently reviewed their Illinois filing positions, particularly service providers who may not have previously considered themselves subject to these rules, should do so in light of these changes.

Source: Illinois Tax Department