Hawaii OS/OD Overview
Permit Required
Yes – any load over legal size or weight needs a permit before it moves, and in Hawaii who issues that permit depends on whose road you are on. HRS 291-36(a): “The director of transportation, in the case of state highways, or the county engineer, in the case of county roads and streets, may, upon application in writing, issue a written permit authorizing the applicant to operate or move a vehicle or combination of vehicles … of dimensions or weights … which exceed the limits set in sections 291-34 and 291-35.” The Hawaii Department of Transportation (HDOT) permits the state highway system under HAR chapter 19-104, whose own scope clause (19-104-1(a)) covers movements “on state highways.” The four counties permit everything else. HDOT's permit form prints it on its face: “(THIS PERMIT VALID ON STATE HIGHWAYS ONLY-OTHER ROUTES SUBJECT TO CITY & COUNTY REGULATIONS).”
Every figure on this page is the state-highway rule, and it is a floor, not a ceiling. HRS 291-36(i): “No provision herein shall be so construed as to prevent the passage of ordinances by any county which impose restrictions more severe in nature.” HAR 19-104-11(7) says the permit “does not relieve the permittee from complying with other existing state and county laws and ordinances which may govern the movement,” and General Condition 10 on the permit form requires the load to be “accompanied with any required escort vehicles in accordance with existing state and county laws and ordinances.” No county escort threshold could be retrieved for Honolulu, Hawai'i, Maui or Kaua'i — those code sites are unreachable or serve empty pages, so this page does not guess at them. If any part of your route is a county road, call the county engineer and get the number from them. HDOT district offices: Oahu (808) 831-6700 x123, Maui (808) 873-3535, Hawai'i (808) 933-8866, Kaua'i (808) 241-3000.
Legal Limits (Without Permit)
- Width: 8'6"
- Height: 13'6" — but the statute and the rule disagree; see the note below
- Length: 65' (combo)
- Weight: 80,000 lbs GVW (standard axle limits apply)
Live conflict on legal height: HRS 291-34(b) sets legal height at 14 feet, while HAR 19-104-14(b)(2) — adopted in 1981 and never amended — still reads 13'6". The statute controls, but 13'6" is the conservative figure to plan against. Separately, HAR 19-104-16 treats an overall length exceeding 70 feet as a move that “is not one of many to be made in the course of regular operations” — that is a permit-type condition, not a legal limit and not an escort trigger. The 65' legal length above is the one figure on this list not re-read from the statute in this pass; confirm it with HDOT.
Travel Hours
HAR chapter 19-104 sets no statewide daylight-only, weekend or holiday window this page can cite. That is a gap in what has been established, not a licence to run at night — treat over-dimensional moves as daylight, fair-weather operations and get the time of day in writing on the permit face. Counties can restrict hours independently on their own roads, and HAR 19-104-11(7) makes the state permit effective only as far as the department's own authority reaches. Do not assume a window that is not printed on your permit.
Who owns the road decides the answer
Hawaii has five permitting authorities and they do not agree, so the first question on any Hawaii move is not how wide the load is — it is whose road it sits on. HDOT's rule below reaches state highways only. The four counties permit their own roads, and none of them adopts HAR chapter 19-104: Honolulu adopts the HRS statute directly (ROH 15-21.8), Kaua'i supplements HRS ch. 291C, Hawai'i County adopts ch. 291C only, and Maui runs a freestanding traffic code. That divergence is deliberate — HRS 291-36(i): “No provision herein shall be so construed as to prevent the passage of ordinances by any county which impose restrictions more severe in nature.” On an island network most of the mileage you actually drive is county road.
The lowest escort threshold in Hawaii is 9 feet, not 12. Honolulu and Kaua'i both require an escort over 9'0" by mandatory ordinance text. A load between 9'1" and 12'0" needs an escort on an O'ahu or Kaua'i county road and does not on a state highway. Check the route before you quote.
County Escort Requirements
| Authority | Escort Requirement |
|---|---|
| City & County of Honolulu (O'ahu) — width over 9'0" | One escort by day, TWO at night. By day: “An escort vehicle, displaying at least one red flag on each side at the front, shall precede such load” (ROH 15-21.13(c)). At night: “such load shall be escorted by at least two escort vehicles, one of which shall precede the load and one of which shall follow the load” (15-21.13(d)). The night case is the normal case — 15-21.13(a) confines over-width moves to 1:00 a.m. to 6:00 a.m. by default; loads under 14' may move any time except 6:30–8:30 a.m. and 3:30–5:30 p.m. The 9 feet is measured “exclusive of eaves or overhangs of less than 3 feet and having a clearance of 10 feet or more above the roadway” (15-21.12(a)) — a low three-foot eave counts against you, a high one does not. Lead spacing is fixed by table on combined speed, 200' at 30 mph rising to 600' at 70 mph; maximum load speed 25 mph. Exempt: military tactical movements and agricultural implements in normal operations (15-21.13(j),(k)). |
| County of Kaua'i — width over 9'0" | One escort by day, TWO at night — KCC 16-19.7(c) and (d), near word-for-word identical to Honolulu's (both date to the late 1960s and share an ancestor). The 9-foot figure sits in the preceding section, KCC 16-19.6(a), “loads in excess of nine (9) feet in width.” The County Engineer may compel paid Police Department escorts where an applicant's own vehicles fail the equipment minimums. |
| County of Maui (Maui, Moloka'i, Lāna'i) | No published threshold — escorts are a per-permit condition. MCC 10.68.010 triggers a permit at dimensions that “exceed the limits set by state statutes,” and the engineer “may issue such a special permit under such conditions of time, route, equipment, speed and otherwise as they may determine.” A keyword sweep of the entire Maui County Code Title 10 returns zero occurrences of “escort.” You cannot pre-compute escort need from dimensions on Maui — ask when you apply. |
| County of Hawai'i (Big Island) | No published threshold and no county oversize permit programme at all. The only pilot-car reference in the county code is definitional — “any pilot car required by permit issued by highway authorities while actually engaged in the movement of extra legal-size vehicles or loads” (HCC 24-3(42)(d)) — and “extra legal-size” is never defined. Call DPW at (808) 961-8321 and HDOT Hawai'i District at (808) 933-8866 before routing. |
Maui and Hawai'i County are silent, not in agreement with the state. Neither adopts HAR 19-104, so the state's 12-foot rule has no force on their roads — do not read their silence as a twelve-foot rule.
Escort Requirements (HAR Chapter 19-104 — State Highways)
| Trigger | Escort Requirement |
|---|---|
| Width over 12'0" — any state highway, any hour | 1 escort vehicle required. “All vehicles or loads exceeding 12 feet in width shall require an escort vehicle.” Position is not fixed by rule — the escort holds station “ahead or behind” the carrier unit, so front versus rear is set on the permit face. HAR 19-104-15(c), with 19-104-28(c) |
| Width over 10'0" — two-lane state highways through mountain or winding coastal terrain | An escort may be required — discretionary, not automatic. “In general, escort vehicle may be required for widths exceeding 10 feet on two-lane roads traversing mountain or winding coastal areas.” HAR 19-104-15(c) |
| Width 14'0" or wider — state highways | The escort vehicle is still mandatory at this width. HAR 19-104-15(b)(4) lets an escort vehicle, flagman or police accompany the move, but that is a condition of issuing the permit — it does not displace 19-104-15(c), which independently requires an escort vehicle for any load exceeding 12 feet. A 14' load exceeds 12 feet, so a flagman or police come in addition to the escort vehicle, never instead of it. Maximum operating speed 25 mph, and the moving contractor must submit a written statement certifying the route has been examined and that there will be at least 1 foot of clearance on each side. HAR 19-104-15(b) |
| Horizontal projection (overhang) more than 4'0" — front or rear | Escort vehicle(s) required. “An escort vehicle shall be required for horizontal projection greater than 4 feet” and “if the projection extends beyond 4 feet, escort vehicles shall accompany the move.” The rule names no direction and uses the plural, so it covers front and rear alike and the count and position come off the permit. HAR 19-104-14(c) and 19-104-18(a) |
| Height — any | No height escort and no height-pole requirement exists anywhere in HAR chapter 19-104. The clearance duty sits on the permittee instead: “The permittee shall check structures and overhead utility lines for available clearance in overheight movements.” HAR 19-104-11(8), with 19-104-17 |
| Length — any | No length-based escort trigger exists. HAR 19-104-16 (Overlength) sets none at any length. HAR 19-104-16 |
| Any dimension, at the district engineer's judgment | A police escort may be required “when in his judgment such escort is necessary to ease the flow of traffic or for public safety.” An additional escort vehicle may also be required “depending upon the character of the road and the traffic volume” — no width figure is attached to it. HAR 19-104-15(c) and 19-104-15(d) |
Four things to get right about this table. First, the governing trigger is over 12 feet wide, and it reads “exceeding,” so a load measuring exactly 12'0" does not trip it and 12'1" does. The 14' tier is the opposite — “14 feet or wider” — so exactly 14'0" does trip that one. Second, Hawaii does not fix the escort's position; 19-104-28(c) says “ahead or behind,” so anyone quoting you a mandatory front car on a Hawaii state highway is quoting the permit, not the rule. Third, Hawaii publishes no second-escort width — 19-104-28(d) is one escort per load (“Generally, separate escort vehicle shall be provided, when required by permit or statute, for each vehicle or load”), and anything beyond that is discretionary with no figure. Fourth, there is no length escort trigger and no height pole in the chapter; if you have seen a Hawaii table showing a front car starting at 16', a chase car at 18', a height pole at 15', or an escort at 100' of length, none of those are in HAR chapter 19-104 — two of them were cited to “HAR 19-120.1” and “HAR 19-120.5,” rule numbers that do not exist, and the 100' figure was cited to HRS 291C-133, which is the statute about waste material falling off trucks. Source: HAR 19-104-14, 19-104-15, 19-104-17, 19-104-18 and 19-104-28.
Detailed Information
ESCORTS: On state highways, the one automatic escort trigger is width over 12'0". HAR 19-104-15(c) verbatim: “All vehicles or loads exceeding 12 feet in width shall require an escort vehicle. However, this shall not preclude a requirement for an escort vehicle in certain areas for loads of lesser width or for an additional escort vehicle depending upon the character of the road and the traffic volume. In general, escort vehicle may be required for widths exceeding 10 feet on two-lane roads traversing mountain or winding coastal areas.” The count is one; a second escort is discretionary and Hawaii attaches no width to it. The position is not set by rule — HAR 19-104-28(c) requires the escort to hold the prescribed distance “ahead or behind” the carrier unit, so front versus rear comes off the permit face. There is no length-based escort trigger in the chapter at any length, and no height-based escort trigger at any height. County roads are a separate regime and may be stricter — verify with the county engineer.
WIDTH 14'0" AND WIDER: This tier is inclusive — exactly 14'0" counts. HAR 19-104-15(b) verbatim: “Permits may be issued to move a vehicle or combination of vehicles, empty or with load, 14 feet or wider, provided: … (3) The maximum operating speed shall be 25 miles per hour; (4) Escort vehicle, flagman or police accompany the move; and (5) A statement is submitted by the moving contractor certifying that the route has been examined and that there will be a clearance of at least 1 foot on each side …” Read limb (4) carefully, because it is not an escape from the escort. 19-104-15(b) is a condition of issuing a permit for a 14'-or-wider move; it does not displace 19-104-15(c), which independently provides that “All vehicles or loads exceeding 12 feet in width shall require an escort vehicle.” A load 14' or wider necessarily exceeds 12 feet, so the escort vehicle is mandatory at this width, and the flagman or police named in limb (4) are additional to it, not alternatives to it. Do not quote a 14'-or-wider Hawaii move without an escort vehicle. The route-examination certificate and the 25 mph cap are separate obligations on top of that, and both have to be planned for before the move is quoted.
OVERHANG / HORIZONTAL PROJECTION: More than 4 feet of horizontal projection requires an escort, front or rear. HAR 19-104-14(c) verbatim: “An escort vehicle shall be required for horizontal projection greater than 4 feet.” HAR 19-104-18(a) verbatim: “Horizontal projections extending 4 feet beyond the extremity of the vehicle are prohibited, and if the projection extends beyond 4 feet, escort vehicles shall accompany the move.” The trigger reads “greater than,” so exactly 4'0" does not trip it. Hawaii states this with no direction, so a front projection triggers it exactly as a rear one does; 19-104-18(a) uses the plural “escort vehicles,” so the count and the position are set on the permit.
HEIGHT POLE: Hawaii imposes no height-pole requirement and no height escort anywhere in HAR chapter 19-104. It puts the clearance duty on the permittee instead. HAR 19-104-17 (Overheight) in full: “Permits may be issued for overheight vehicles and loads if the movement can be made without seriously jeopardizing other traffic, public utility or highway facilities. The maximum height of a vehicle or vehicle and load for which a permit may be issued is governed by available overhead clearances throughout the route, which assurance is the responsibility of the permittee.” HAR 19-104-11(8): “The permittee shall check structures and overhead utility lines for available clearance in overheight movements.” Survey the route and every utility crossing yourself; HDOT publishes bridge-clearance lists off its Trucking page. Carrying a pole on an over-height Hawaii move is good practice — it is not a rule you can cite, and it will not excuse a clearance strike.
LENGTH: HAR 19-104-16 (Overlength) sets no escort trigger at any length. Its only figure, 70 feet, is a permit-type condition: “When the overall length exceeds 70 feet, the move is not one of many to be made in the course of regular operations.” The “100 feet” figure that circulates on Hawaii escort tables comes from HRS 291-36(k)(4) and HAR 19-104-27(c)(4), where “not more than one hundred feet” caps the length of agricultural equipment crossing a road without a permit — an exemption, the opposite of an escort mandate. A county may impose a length escort this page cannot see; on a county road, ask.
POLICE ESCORT: Discretionary, with no dimensional trigger. HAR 19-104-15(d): “The district engineer may require police escort when in his judgment such escort is necessary to ease the flow of traffic or for public safety.” Under 19-104-15(b) a police unit can also stand in for the escort vehicle on a load 14' or wider.
COUNTY ROUTES: Hawaii oversize moves routinely cross both state highways and county roads, and the two are governed by different agencies under different rules. HRS 291-36(a) gives county roads and streets to the county engineer; HRS 291-36(i) lets any county impose “restrictions more severe in nature” than the state's. The state-highway figures above are therefore a minimum, not an answer, for any county mileage. No county's escort thresholds could be retrieved for this page — Honolulu's code index and its replacement both fail, the Maui code site serves an empty JavaScript shell, and the Hawai'i County and Kaua'i sites refuse automated requests. Call the county engineer for the island you are running: Oahu (808) 831-6700 x123, Maui (808) 873-3535, Hawai'i (808) 933-8866, Kaua'i (808) 241-3000.
Additional Notes
- Extremity marking is a permit condition, not just good practice — permit form DOT 4-005, General Condition 10: “The extremities of an oversize vehicle or load shall be marked with flags and lights and be accompanied with any required escort vehicles in accordance with existing state and county laws and ordinances”
- Escort spacing is set by HAR 19-104-28(c), which requires the escort to maintain a prescribed distance ahead or behind the carrier unit — the rule contemplates either position
- One escort per load is the baseline (HAR 19-104-28(d)): “Generally, separate escort vehicle shall be provided, when required by permit or statute, for each vehicle or load”
- HAR chapter 19-104 took effect May 30, 1981 and is still listed by HDOT as a current rule; where it conflicts with a later statute — as it does on legal height — the statute controls
- Permit conditions issued for the specific move govern and may impose requirements beyond these thresholds; HAR 19-104-11(7) preserves every other state and county law on top of them
- Rule numbers to distrust: HAR 19-120.1 and 19-120.5 do not exist. HDOT's current-rules index runs 19-101 through 19-109 and then 19-121 through 19-154. HRS 291C-133 is real but is “Waste material falling from motor vehicles”
Sources: HAR Chapter 19-104 — Movement by Permit of Oversize and Overweight Vehicles on State Highways (the rule text; note this PDF is scanned images, so text search and link checkers will find nothing in it) and HDOT Guide to Permits. Informational only — always verify against the live permit office before any move; permit conditions control. These are state-highway figures only. County roads are permitted by the county engineer and may be stricter, and no county's thresholds are published here — confirm with the county DPW or county engineer for any portion of the route off the state system.
