IFTA Tax Rates in South Dakota (2026)

Key numbers at a glance

IFTA tax rates in South Dakota

South Dakota's IFTA rate is $0.28 per gallon on gasoline and diesel, per the Q4 2026 IFTA Inc. matrix. The full pump picture is 30 cents: the South Dakota Department of Revenue lists the base fuel excise plus a 2-cent petroleum release compensation fund fee, and the Tax Foundation's July 2026 table carries the combined $0.3000 for both fuels. For the IFTA return, the matrix figure — 28 cents — is the one that matters. Rates below are as of Q4 2026 — confirm the current official IFTA matrix before filing.

The rate has been stable by design. The 2015 legislation that set it included an annual escalator, but the escalator has been suspended, leaving the excise flat at 28 cents (30 with the fee) for years. Flat, equal across fuels, and no surcharge — the SD line of your return is one of the easiest to estimate in advance.

The Dakotas gap is the local detail: 23 cents in the north versus 28 in the south means every gallon filled in South Dakota pre-pays 5 cents more IFTA credit than the same fill in North Dakota — worth about $7.50 on a 150-gallon stop, before comparing the pretax price.

How South Dakota IFTA affects your filings

The arithmetic for a long haul across the state is straightforward. At 6.5 MPG, a 1,000-mile I-90 transit of South Dakota — Sioux Falls to the Wyoming line and back — burns about 153.8 gallons, which at the 28-cent matrix rate is roughly $43.06 of SD fuel tax. Fuel bought inside the state covers that line gallon for gallon; fuel hauled in from a cheaper-tax stop leaves the gap as tax due. Run your specific lane splits through the IFTA calculator each quarter rather than guessing.

Strategically, South Dakota is a buy-to-burn state in the Plains context: its 28 cents beats the rates east and south of it (Ohio's 47-cent diesel, North Carolina's 41) while losing to its northern sibling's 23. That makes the standard IFTA logic apply with a Plains accent — fill in South Dakota for the miles you will burn in the region, but when the load points toward Pennsylvania or the Northeast, do the heavy fueling there, where a 74.1-cent diesel rate pre-pays credit you would otherwise owe state by state. Always compare pump price minus tax; a 2-cent fee difference or a 5-cent rate gap is easily swamped by retail pricing between truck stops.

Compliance is where Plains carriers most often stumble, because long low-tax miles invite sloppy records. Auditors still want fuel receipts without gaps, per-state distances from the ELD, your MPG calculation, and typically four consecutive quarters of returns. Deadhead miles count toward distance records too — see our deadhead miles guide for how empty miles quietly change both revenue and IFTA geography. File by April 30, July 31, October 31 and January 31 even when the net is zero, set your fuel surcharge against after-tax cost, and keep the IFTA rates by state hub handy for the rest of the map.