What Iowa charges for a single-trip OS/OW permit, the limits that trigger one, and the escort thresholds — read from the state’s own publication. This rule has been in effect since 2026-07-09; we last read the source on 2026-07-09.
Oversize permit
$35
One price for a single-trip permit, whatever the dimensions. A 9-foot-wide load and a 16-foot-wide load pay the same.
Overweight permit
From $35
Scales with weight — there is no single figure.
A load that is both oversize and overweight pays this fee only, not both.
+ $20 Permigo service fee per permit, state fees at cost.
Legal limits
Exceed any one of these in Iowa and you need a permit for this state.
Limit
Interstate
Width
8'6"
Height
13'6"
Length
75'0"
Gross weight
80,000 lbs
Single axle
20,000 lbs
Tandem axle
34,000 lbs
Trailer length
53'0"
What the permit costs
Iowa prices a single-trip permit as flat rate. One price for a single-trip permit, whatever the dimensions. A 9-foot-wide load and a 16-foot-wide load pay the same.
Escort requirements
Thresholds by road class. Where two classes differ, the road you are actually on governs.
4+ lane (divided)
Width
Requirement
Over 12'0"
1 rear escort, or amber light>12'–14'6" wide: 1 rear (four-lane) escort OR the amber-light/strobe substitute (asterisked row — IA permit-printed provisions table (identical on 3 real 2026 permits), verbatim rows: "Over 12' up to and including 14'6\": Rear* (four-lane) / Front* (two-lane)"; "Over 14'6\" up to and including 16'6\": Rear* / Front"; "Over 16'6\" up to and including 18': Rear / Front"; footnote: '*In lieu of an escort, a vehicle can display an amber light or strobe on the power unit and on the rear extremity of the load.').
Over 14'6"
1 rear escort, or amber light>14'6"–16'6" wide on four-lane: 1 rear escort OR the amber-light substitute (asterisked).
Over 16'6"
1 rear escort>16'6"–18' wide: 1 rear (four-lane) escort, not substitutable. The printed table ends at 18' — wider is beyond the routine provisions (superload/discretionary; this band
Over 18'0"
Conditions applyWidth over 18' falls OFF the escort table (511.20(2) ends at 18') — escorts and movement conditions are set case-by-case by the permit authority, which 'may require additional escorts when deemed necessary' (511.20(4)). Iowa has no superload class or fee: the $35 + $4/ton formula still applies; the gate is discretion, not price.
Height
Requirement
Over 14'6"
1 front escort · height poleOver 14'6" to 20' tall: ONE front escort WITH a height pole — 'A pole used for measuring vertical clearances is mounted on the front escorting vehicle' (IAC 511.20(1)(j); table: 'front with a height pole' on both road types). One vehicle, one bill
Over 16'0"
Conditions applyOver 16'0": the carrier must contact affected public utilities; written verification at the permit authority's discretion (IAC 511.13(1)(c) — a single-trip-rule condition, not an escort rule).
Length
Requirement
Over 85'0"
Marking requiredOver 85'0" overall up to 120': amber strobe lights required on the towing unit (flags/signs + lights YES per IAC 761-511.20(2)), but NO escort vehicle yet. The escort-vehicle trigger does not apply until over 120'. Trigger >85'0" = 85'1"+.
Over 120'0"
1 rear escortOver 120'0" overall: 1 rear escort on all road types (IAC 761-511.20(2): 'Over 120' — 4-lane rear / 2-lane rear'). No second escort is triggered by length alone (IA.md row 18). Above 120' the load exceeds the annual/multi-trip length cap and must use a single-trip permit (no superload tier). Trigger >120'0" = 120'1"+.
Front overhang
Requirement
Over 25'0"
Marking requiredFront overhang over 25'0": amber strobe lights required, but NO escort vehicle (IAC 761-511.20(2): 'Front: over 25' — lights yes'). Iowa Code §321.458 caps general front load overhang at 3' beyond the front wheels/bumper; over-3' front overhang needs a permit but triggers no escort by itself. Trigger >25'0" = 25'1"+.
Rear overhang
Requirement
Over 10'0"
Marking requiredRear overhang over 10': flags AND amber/strobe lights — 'escorts not required' (IAC 511.20(2) verbatim;)
Weight
Requirement
Over 100,000 lbs
Conditions applyGross over 100,000 lb: single-trip issuance is DISCRETIONARY — 'a single-trip permit may be issued for the movement only if the permit-issuing authority determines that it would not cause undue damage to the road and is in the best interest of the public' (IAC 511.17(4)(b)). No absolute gross cap for single trips; bridge protection per §321E.9(1). Permitted tandems may carry 46,000 (4 tires/axle, ≤24k per axle, centers ≤96", §321E.7(1)(e)).
2/3 lane (undivided)
Width
Requirement
Over 12'0"
1 front escort, or amber light>12'–14'6" wide: 1 front (two-lane) escort OR the amber-light/strobe substitute (asterisked row — IA permit-printed provisions table (identical on 3 real 2026 permits), verbatim rows: "Over 12' up to and including 14'6\": Rear* (four-lane) / Front* (two-lane)"; "Over 14'6\" up to and including 16'6\": Rear* / Front"; "Over 16'6\" up to and including 18': Rear / Front"; footnote: '*In lieu of an escort, a vehicle can display an amber light or strobe on the power unit and on the rear extremity of the load.').
Over 14'6"
1 front escort>14'6"–16'6" wide on two-lane: 1 FRONT escort — NOT substitutable (no asterisk on this cell).
Over 16'6"
1 front escort>16'6"–18' wide: 1 front (two-lane) escort, not substitutable. The printed table ends at 18' — wider is beyond the routine provisions (superload/discretionary; this band
Over 18'0"
Conditions applyWidth over 18' falls OFF the escort table (511.20(2) ends at 18') — escorts and movement conditions are set case-by-case by the permit authority, which 'may require additional escorts when deemed necessary' (511.20(4)). Iowa has no superload class or fee: the $35 + $4/ton formula still applies; the gate is discretion, not price.
Height
Requirement
Over 14'6"
1 front escort · height poleOver 14'6" to 20' tall: ONE front escort WITH a height pole — 'A pole used for measuring vertical clearances is mounted on the front escorting vehicle' (IAC 511.20(1)(j); table: 'front with a height pole' on both road types). One vehicle, one bill
Over 16'0"
Conditions applyOver 16'0": the carrier must contact affected public utilities; written verification at the permit authority's discretion (IAC 511.13(1)(c) — a single-trip-rule condition, not an escort rule).
Length
Requirement
Over 85'0"
Marking requiredOver 85'0" overall up to 120': amber strobe lights required on the towing unit (flags/signs + lights YES per IAC 761-511.20(2)), but NO escort vehicle yet. The escort-vehicle trigger does not apply until over 120'. Trigger >85'0" = 85'1"+.
Over 120'0"
1 rear escortOver 120'0" overall: 1 rear escort on all road types (IAC 761-511.20(2): 'Over 120' — 4-lane rear / 2-lane rear'). No second escort is triggered by length alone (IA.md row 18). Above 120' the load exceeds the annual/multi-trip length cap and must use a single-trip permit (no superload tier). Trigger >120'0" = 120'1"+.
Front overhang
Requirement
Over 25'0"
Marking requiredFront overhang over 25'0": amber strobe lights required, but NO escort vehicle (IAC 761-511.20(2): 'Front: over 25' — lights yes'). Iowa Code §321.458 caps general front load overhang at 3' beyond the front wheels/bumper; over-3' front overhang needs a permit but triggers no escort by itself. Trigger >25'0" = 25'1"+.
Rear overhang
Requirement
Over 10'0"
Marking requiredRear overhang over 10': flags AND amber/strobe lights — 'escorts not required' (IAC 511.20(2) verbatim;)
Weight
Requirement
Over 100,000 lbs
Conditions applyGross over 100,000 lb: single-trip issuance is DISCRETIONARY — 'a single-trip permit may be issued for the movement only if the permit-issuing authority determines that it would not cause undue damage to the road and is in the best interest of the public' (IAC 511.17(4)(b)). No absolute gross cap for single trips; bridge protection per §321E.9(1). Permitted tandems may carry 46,000 (4 tires/axle, ≤24k per axle, centers ≤96", §321E.7(1)(e)).
Movement restrictions
Restriction
In Iowa
Night travel
Daylight hours only
Weekends
Not specified
Holidays
Restricted
Movement hours (IAC 761-511.3 + §321E.11, verified 2026-07-09)
Memorial, Independence, Labor Day: no movement on the day, after NOON the day before, and through the holiday WEEKEND when it falls Fri–Mon (no Thanksgiving/Christmas/New Year blackout — aggregators overstate)
Weekends
open outside holiday weekends
Weather
roads clear of ice/snow + visibility ≥¼ mile (511.3(2))
Where these permits come from
If you file yourself, this is the office you are dealing with. Check the linked page — some states issue OS/OW permits through their highway patrol or revenue department rather than the DOT.
