What Navionics Cards Are and How They Fit Into Your Setup

Navionics cards are digital map files you load onto a GPS device or chartplotter to see depth contours, structure, and navigation data on the water. They come as microSD cards or as software licenses you download, depending on your device. Unlike paper maps, they update regularly and let you mark waypoints, routes, and fishing spots that stay saved to your device.

If you already own a GPS unit or a boat with a chartplotter, a Navionics card is what turns that blank screen into a working map. The card itself is just the storage medium — the real value is the chart data Navionics has compiled from government surveys, satellite imagery, and user contributions over decades.

Navionics makes several product lines. Navionics Plus covers coastal and inland waters with depth contours and structure detail. Navionics+ Sonar adds high-resolution sonar imagery so you can see the actual lake or river bottom. Navionics HotMaps is an older line still in use on many devices. Which one you need depends on what device you own and what waters you fish.

Key Takeaways

  • Navionics cards load onto compatible GPS units and chartplotters as microSD cards or digital licenses, giving you detailed depth maps and structure data on the water.
  • Navionics Plus covers most inland and coastal fisheries with contour lines and bottom composition; Navionics+ Sonar adds photorealistic lake-bottom imagery for an extra cost.
  • Your device must be compatible with Navionics — not all GPS units accept Navionics cards, so check your device manual or Navionics' compatibility list before buying.
  • Navionics charts update several times per year, and you can download updates to your card or device through Navionics' software or your device's built-in update function.
  • Navionics cards cost between $30 and $150 depending on coverage area and product tier, and many are sold as one-time purchases rather than subscriptions.

Which Navionics Product Matches Your Fishing Style

Navionics Plus is the standard choice for most freshwater and coastal anglers. It shows depth contours at intervals (typically 5 feet, 10 feet, 20 feet, and so on), structure like drop-offs and humps, and bottom composition where available. You can mark your own waypoints and save routes. For lakes and rivers where you already know the general layout, Plus is usually enough.

Navionics+ Sonar is worth the extra cost if you fish large, unfamiliar reservoirs or if you want to see exactly what the bottom looks like before you commit to a spot. The sonar imagery shows you sand, rock, vegetation, and depth in photorealistic detail — essentially a picture of the lake floor. This is most useful on new water or when you are scouting structure you cannot see from the surface.

Navionics HotMaps is an older product line that still works on many older Garmin and Lowrance units. If your device is more than five years old, you may only have access to HotMaps. The coverage and detail are less current than Plus, but they still show depth and basic structure.

Navionics also sells regional cards — for example, separate cards for the Great Lakes, the Mississippi River system, or the Pacific Northwest. If you fish one region consistently, a regional card is cheaper than a nationwide option and often has finer detail for that area.

Device Compatibility and How to Check Before You Buy

Not every GPS or chartplotter accepts Navionics cards. Garmin, Lowrance, and Humminbird all support Navionics, but older models may not, and some newer units use proprietary map formats instead. Before you spend money, check three things: your device manual, the device manufacturer's website, or Navionics' own compatibility checker on their website.

If your device is compatible, you also need to know what format it accepts. Most modern units take microSD cards directly. Some older units need a specific card type or size. A few devices only accept Navionics through a digital license you download into the device's built-in memory — no physical card required. Your manual will say which applies to you.

Navionics also makes software for smartphones and tablets through their mobile app, which works on iOS and Android. The mobile app is cheaper than a chartplotter card and works well for planning trips or checking a spot before you head out, but most anglers use it as a supplement to a dedicated GPS unit rather than a replacement.

How to Install and Update Your Navionics Card

Installation depends on your device type. If you have a microSD card, you insert it into the card slot on your GPS or chartplotter — the same way you would insert an SD card into a camera. The device recognizes it automatically and adds the charts to your map menu. No software installation needed.

If you bought a digital license instead of a physical card, you download the chart data through Navionics' software (called Navionics Boating or Navionics Fishing, depending on your subscription) or through your device's built-in update function. This process varies by device, so follow your manual or the on-screen prompts.

Navionics updates its charts several times per year as new survey data comes in and users report corrections. You can update your card by connecting it to a computer and running Navionics' update software, or by connecting your device to WiFi and letting it download updates automatically. Check your device settings to see if auto-update is turned on.

Cost, Coverage Areas, and What You Actually Get

Navionics Plus cards typically cost between $30 and $100 depending on the region. A card covering a single state or a major lake system costs less than a nationwide card. Navionics+ Sonar cards cost more — usually $80 to $150 for the same coverage — because the sonar imagery requires more data storage and processing.

Most Navionics cards are sold as one-time purchases, not subscriptions. You buy the card once, and you own it. Updates are free. If you want to fish a different region later, you buy a new card for that region. Some anglers keep two or three cards in rotation depending on where they are fishing.

Navionics also offers a subscription service called Navionics+ Premium for boaters who want unlimited access to all charts nationwide and automatic updates. This costs more upfront but works well if you travel to different regions frequently or if you want the simplest update process.

The coverage area varies by card. A "Great Lakes" card covers all five Great Lakes plus connecting waters. A "Florida" card covers the entire state. A "Nationwide" card covers the continental United States but with less detail in any single region than a regional card would. Check the product description to see exactly which waters are included before you buy.

Common Reasons Anglers Choose Navionics Over Paper Maps

Navionics charts update regularly, whereas paper maps become outdated as soon as they are printed. If a new marina opens, a channel is dredged, or a hazard is discovered, Navionics can push that information to your device within weeks. Paper maps cannot.

You can mark and save unlimited waypoints on a Navionics card — your favorite fishing spots, launch ramps, fuel docks, or hazards. Those marks stay on your device and sync across your devices if you use Navionics' cloud service. On a paper map, you write in pencil and erase it when you move on.

Navionics integrates with your device's sonar or fish finder if you have one. Your GPS can overlay your sonar returns on the Navionics chart, so you can see what the bottom looks like in real time and compare it to the chart's contour lines. This combination is far more powerful than either tool alone.

Limitations and When Navionics May Not Be Enough

Navionics charts are only as accurate as the survey data they are built from. On some smaller lakes or remote rivers, the depth contours may be 20 or 30 years old. The chart will still show you the general shape of the lake, but the exact depth at a specific spot might be off by a few feet. Always verify with your own sonar before committing to a spot.

Navionics does not show real-time water level, current, or weather. You need a separate weather app or your local water authority's website to know if a river is high or low. On reservoirs that fluctuate seasonally, the chart shows the contours at full pool — if the water is down, the actual shoreline will be different from what the chart shows.

Navionics charts also do not include fishing-specific information like which species are in which part of a lake or what the bite is like right now. They are navigation and structure tools, not fishing reports. You still need local knowledge, a fishing app, or conversations with other anglers to know where the fish are.

Frequently Asked Questions

Can I use the same Navionics card on two different devices?

Not usually. A physical microSD card can only be in one device at a time. If you own a digital license, you may be able to install it on two devices depending on your subscription terms — check Navionics' license agreement. Most anglers buy separate cards for each device or transfer the card between devices as needed.

Do I need WiFi or cell service to use a Navionics card on the water?

No. Once the chart is loaded onto your device, it works completely offline. You do not need a signal to see the map or navigate. You only need WiFi or cell service if you want to download updates or sync your waypoints to the cloud.

What is the difference between Navionics Plus and Navionics+ Sonar?

Navionics Plus shows depth contours and structure as lines and colors on a map. Navionics+ Sonar adds photorealistic sonar imagery so you can see the actual bottom composition — sand, rock, vegetation, mud — as if you were looking at a photograph. Sonar costs more but is worth it on unfamiliar water.

How often do Navionics charts update?

Navionics updates its charts several times per year as new survey data becomes available. You can download updates to your card or device for free. Most devices can be set to auto-update over WiFi, or you can manually check for updates through Navionics' software.

Will an old Navionics card still work on a new device?

It depends on the device and the card format. If your new device accepts the same card type as your old device, the card will work. If your new device uses a different format or only accepts digital licenses, you will need to buy a new card. Check your new device's manual to see what formats it supports.