Autopilot IP Rating: Waterproofness Guide
Short answer: An IP rating, short for Ingress Protection, describes how well an electronic unit resists solids and water using a two-digit code: the first digit for dust and the second for water. In an autopilot system, the control head at the helm or cockpit faces the most spray, so it carries the highest water rating in most systems. A course computer or actuator control unit sits below deck and needs less. The exact rating for a unit is stated by the maker, not in the stated details this site compares.
What an IP rating means
An IP rating, short for Ingress Protection, is the code a maker uses to state how well an electronic unit resists solids and water. For a boat owner choosing an autopilot, the rating answers a practical question: which parts of the system can live in the open cockpit and which should sit below deck. The code appears in makers' specification pages and in product manuals, not always in a listing.
The two digits of an IP code each describe one kind of protection. The first covers solids, mainly dust and sand. The second covers water, from light spray to full immersion. A higher digit within either category means a stronger level of protection. Reading the full code, not just one digit, is the way to compare two components.
Where each autopilot component sits on the boat
Autopilot components are not mounted in one place, so they do not share one protection need. The part most exposed on most boats is the control head, because it has to sit where you can reach it: at a helm, on a pedestal or in the cockpit. The course computer or actuator control unit is usually placed below deck and out of the weather. The drive unit sits near the steering gear, often under the cockpit or in a machinery space.
- Control head: at the helm or cockpit, facing spray, rain and sun.
- Course computer or actuator control unit: below deck in a locker, console or cabin.
- Drive unit: near the steering system, under a cockpit sole or in an engine space.
- Tiller pilot: clamped to the tiller in the open cockpit, fully exposed.
The first digit: protection from solids
The first digit of an IP code describes protection from solids. On a boat, the practical concerns are dust, sand and salt crystals rather than large objects. A below-deck course computer sits in an environment where dust from a bilge or an engine space can settle on it, so a degree of solid protection matters there. A cockpit control head is less at risk from dust but takes far more water.
When a specification page shows the full code, look at both digits. A unit with a high water digit but a low solid digit may be fine in an open cockpit yet a poor choice for a dusty machinery space. The location of each component, not the brand, should decide what you accept.
The second digit: protection from water
The second digit is the one that drives most buying decisions, because deck-mounted parts face water directly. Water protection is usually described in steps: protection from dripping, from spray, from splashing, from powerful jets and from immersion. A control head at an open helm deals with spray and rain every time the boat moves. A tiller pilot clamped in the cockpit faces the same conditions.
A below-deck course computer still meets moisture in a marine environment, but it is not struck by direct spray. That is why the highest water digits in an autopilot range are usually reserved for control heads and cockpit units, while a lower digit is acceptable for parts that live inside the boat. The exact digit for a specific unit is stated on the maker's page, which is the source a buyer should check.
Matching the rating to the mounting location
The table below summarizes the usual locations and the level of protection to look for in each. Use it as a starting point, then confirm the maker's stated rating before you order.
The exact rating for a given model is a specification from the maker, not part of the stated details this site's catalogue carries. When a listing does not show a rating, the maker's page and the manual are the two places to confirm it. For the full product range on complete packs, the control head in the box is the part to check first.
| Component | Typical location | Protection to look for |
|---|---|---|
| Control head | Helm or cockpit, in the open | The highest water rating in the system |
| Tiller pilot | Clamped to the tiller in the cockpit | A rating made for direct spray and rain |
| Course computer or ACU | Below deck, in a locker or console | Basic water protection, with solid protection for dusty spaces |
| Drive unit | Near the steering gear, often under the cockpit | Spray from hatches plus moisture in a machinery space |
Why listings and the catalogue may leave IP ratings out
Most autopilot listings and the marine autopilot guides on this site are built from a short set of stated details so that listings can be compared without guessing. An IP rating is not in that set. That does not make the rating unimportant; it makes it a question to take to the maker.
The useful habit is to read the rating on the maker's page before you choose between two packs that otherwise look the same. If you keep an existing drive and add a new control unit, the same rule applies, and the choice between a core pack and a complete pack does not change where the control head sits.
Questions to ask before you buy
Before you order, run through these questions with the listing in front of you and the maker's page open. The answers decide which pack, control head or tiller pilot fits your deck layout.
- Where will the control head sit on your boat, and how much spray does that spot receive?
- What water rating does the maker state for the control head in the pack you are comparing?
- For a tiller pilot, is the rating meant for continuous cockpit exposure?
- Does the course computer go in a dry locker or a space that sees bilge moisture?
- What does the maker's manual say about mounting locations in relation to the rating?
- If the listing carries no rating, ask the dealer for the maker's specification page.
What to pick for your situation
| If you | Pick | Buying guide |
|---|---|---|
| You mount the control head in an open cockpit | A control head whose maker states a high water rating | Best Autopilot with Control Head (2026): 12 Picks Compared |
| You are choosing a tiller pilot for a small sailboat | A tiller pilot made for cockpit use, with the rating confirmed on the maker's page | Best Tiller Pilots for Sailboats in 2026: 6 Picks Compared |
| You compare complete packs that include a control head | The pack whose control head rating matches your helm location | Best Complete Autopilot Packs (2026): 13 Picks Compared |
| You keep an existing drive and buy a core pack | A core pack whose control head suits the deck location | Best Autopilot Core Packs 2026: 12 Picks Compared |
| You want a broad starting point | The general guides first, then the maker's page for the exact rating | Best Marine Autopilot (2026): Marine Autopilot Reviews |
Questions
What does IP mean in an autopilot listing?
IP stands for Ingress Protection. It describes how well a component resists solids and water, using a two-digit code.
Which autopilot part needs the highest water rating?
The control head at the helm or cockpit, and a tiller pilot in the cockpit, because those parts face spray and rain directly.
Does a below-deck course computer need a high rating?
Not the same high rating as a deck-mounted head, but it still needs protection from moisture and dust in a machinery space.
Why is an IP rating not in this site's listing details?
The stated details this site compares are steering type, boat type, drive in the box, control head in the box, model line and brand. The maker's page states the rating.
Does an IP rating say anything about installation?
No. Mounting and wiring are separate questions answered by the maker's manual and carried out by a qualified installer.
Recent updates
- : First published.