What brand/model of GPS do I need?

Our maps are currently only compatible with Garmin GPS Units. Your Garmin unit must accept a 1GB or larger microSD or SD expandable memory card. It is also recommended that you have a color screen to take advantage of our custom color maps. Nuvi automotive units are also compatible with our maps. Please see our Older/Newer Generation Garmin FAQ for more information.

Is my Garmin older or newer generation?

Older generation units are not compatible with the Easy Install option. Please purchase an installer for older units.

Compatible Older Generation Garmin Units (SD card or installer download required)
eTrex models Legend Cx, Legend HCx, Venture Cx, Vista Cx, Vista HCx
Other handheld models 60 Cx, 60 CSx, 76 Cx, 76CSx, Rino 520 HCx, Rino 530 HCx
Nuvi models Any Nuvi with three numbers in the model name Example: Nuvi 265, Nuvi 500, Nuvi 850 (Older Nuvi Models ONLY compatible with Basemaps. NOT compatible with transparent overlays)

Compatible Newer Generation Garmin Units (SD card, installer or “Easy Install”)
Handheld models Astro, Dakota, Colorado, Oregon, Montana, 62, 64, 78, eTrex 20/30, eTrex Touch, Rino 650, Rino 655t, Rino 700, Monterra, all other handheld units since 2008.
Nuvi models Nuvi 42 & 52 and any Nuvi with four numbers in the model name. Example: Nuvi 1100, Nuvi 1490, Nuvi 3790


Installer for Windows or MAC vs. the Easy Install option?

We’ve developed a way to make sure everyone, regardless of your computer comfort level, can download and install our maps on a Garmin GPS unit.


The Easy Install option is ONLY for new generation Garmin units. It will allow you to simply drag and drop already compiled and renamed map .img files onto your blank microSD or GPS units internal memory. No installers or software packages required. Simply drag and drop! You will still be able to view your maps in BaseCamp when you have your GPS or microSD card connected to your computer.


The Windows and MAC installer options allow you to load the mapsets into Garmin software on your computer. You can then send the mapsets to your GPS unit through Garmin’s software. If you own an older generation Garmin GPS unit you will need to purchase an installer.

WINDOWS Installer – How To

To install our maps onto your WINDOWS computer for use in BaseCamp, simply follow the steps below.

You must have Garmin BaseCamp for WINDOWS installed before proceeding.

INSTALLING THE DOWNLOAD on Windows computer running XP, Vista, 7, or 8.
  1. Close any Garmin mapping program (BaseCamp, MapSource) that may be open before proceeding.
  2. Download the map installer zip file and unzip (right click, extract all)
  3. Inside the unzipped folder you will see the installer file (.exe extension). Double click on the installer file to install the map(s).
  4. Open Garmin’s BaseCamp program and follow Garmin’s instructions to upload the mapsets to your GPS unit or SD card.



MAC Install Files – How To

Installing our maps onto your MAC computer is easy. Simply follow the steps below.

You must have Garmin BaseCamp for MAC installed before proceeding.

Installing MapManager
  1. On your Mac computer, go to www.garmin.com/mapmanager.
  2. Click on ‘Download’ and choose to save the file to your computer.
  3. Double-click the file to open it.
  4. A new Finder window will open. Locate and double-click on the ‘Install Garmin MapManager’ icon.
  5. Follow the installer program’s prompts to install Garmin MapManager.
Opening and Installing Maps   
  1. Unzip the downloaded map file (will have a “gmapi.zip” file extension)
  2. Browse to the location where you unzipped your map install files. Map files have a Garmin map file icon and a “.gmapi” file extension.
  3. Double-click on a map file you want to install. MapManager launches and the map installation dialog box appears.
  4. Click Install.
  5. Repeat steps 1–3 for all maps you want to install.
Now you’re ready to open BaseCamp or MapSource and begin uploading maps to your GPS!
If you have any questions or need help please don’t hesitate to contact us at gpsmapsmontana@gmail.com


The Easy Install option is compatible with newer Garmin models. The Easy Install file is a pre-compiled, properly formatted map file or files that can be easily transferred to a micro SD chip (drag-n-drop). Once the file is placed on the chip, your ready to roll. You can also view the map data in BaseCamp whenever your GPS is connected to your computer. The Easy Install option lets you skip dealing with the installer and software for those less inclined to do so. Simply download, drag-n-drop, and turn the unit on! All the work of compiling and renaming different mapsets is already done for you.

Easy Install compatible Garmin units
Handheld models: Dakota, Colorado, Oregon, Montana, 62, 64, 78, eTrex 20/30, eTrex Touch, Rino 650, Rino 655t, Monterra
Nuvi models – Nuvi 42 & 52 and any Nuvi with four numbers in the model name. Example: Nuvi 1100, Nuvi 1490, Nuvi 3790.

The following steps will get your GPS loaded up and ready to go.

1) Download and unzip the Easy Install file.

2) Connect an SD card, or GPS with the SD card installed, to your computer and create a new folder on the SD card and name it “garmin” (if one doesn’t already exist).

3) Copy and paste the “.img” file(s) from the download folder into the “garmin” folder on your SD card.


4) Insert the SD card into your GPS and view maps!


After the above steps are complete, you can connect the GPS to your computer and open the Garmin BaseCamp program. The maps will load into BaseCamp from your GPS, and be viewable on the computer screen!

If you have any questions or require assistance please don’t hesitate to contact us at gpsmapsmontana@gmail.com



Pre-installed Micro SD

We offer a pre-installed Micro SD card option for our Hunting & Fishing Combo. When you receive your SD card in the mail simply install it into your GPS, power it up, and off you go. Upon placing an SD card order someone here at GPSmapsMontana will email you and ask what model Garmin GPS your using which allows us to properly format your card. Please allow up to 10 business days to receive your product. All orders will be sent via USPS.

All maps on the SD card can be viewed in BaseCamp if your GPS is connected to your computer.

How do I view the maps in BaseCamp?


The “Map Products” dropdown window allows you to change the map visible in BaseCamp.
If you don’t see the “Map Products” window, simply right-click along the top menu bar and click on “Map Products” to enable the dropdown list. (see image below).
If you have a map selected but don’t see any map detail, try adjusting the “Detail Level” via the dropdown list (similar to Map Products) or zoom in on the map.

How do I use BaseCamp to send maps to my GPS?


1. Connect the GPS, with the SD card installed, to the computer and open BaseCamp (SD card only method described at the bottom of the page). Right-click on “User Data” to install to Memory Card and the MapInstall program will open. (see image below)



2. Check the box next to each map product you wish to install and click Continue. If you do not see a purchased map product in the main list, click on the “Advanced/Partial” button. (see image below)Untitled


3. To install maps via the “Advanced/Partial” menu, select the map product from the dropdown list located below the map window. Select all map tiles associated with each product in the map window for a full install. When finished, hit continue. BaseCamp will automatically detect which map format is appropriate for your Garmin model and install them accordingly. (see image below)4Untitled


SD CARD ONLY (GPS not connected):

Newer Generation Units –

If you’re using an SD card plugged directly into your computer (not in your GPS), you will use BaseCamp to load the maps, but only load one mapset at a time. After each download you’ll see a file called “gmapsupp.img” on your SD card. Rename that .img file after the map you just downloaded. For example “MT Topo + Land Owner 2016.img”. If you don’t rename the file, you’ll end up overwriting that gmapsupp with the next mapset. This method is faster than with the GPS connected but requires a bit more attention in properly renaming the files.

Older Generation Units –

Using just the SD card pluged in to your computer (without the GPS), make sure you don’t already have maps on your SD card. This process will overwrite them (blank card recommended). Using BaseCamp as described above, select the desired map tiles from each map in the products list. You will load all the different mapsets at once. Do not rename the gmapsupp.img file.

Click on the following link to read more about map management for specific Garmin models.

If you have questions or require assistance please don’t hesitate to contact us at:

How can I reduce clutter on my GPS screen?

Our mapsets contain vast amounts of information. One reason we seperate some of our mapsets into individual maps is to allow you to enable/disable layers based on your current activity and needs. If your map screen looks cluttered try disabling the maps or overlays you don’t currently need. Another tip to de-clutter your map screen is to adjust the map detail level on your GPS. You can find that setting in your map setup menu. We recommend using the “Normal” map detail setting but you may desire to change that setting if your map screen is still too cluttered.

You can also try turning off map labels, a setting that can also be found on the GPS in the map setup menu. We find that turning off the “Landcover” text (topo line and polygon labels) and “Street Names” text goes a long way in improving the map display.

If you own a newer generation unit try turning off the elevation or terrain shading. Turning off terrain shading will change the default map background color from tan to white, making any map much easier to view in bright sunlight.

The topo map isn’t showing up on my GPS map screen.

Below are the most common reasons for not seeing our maps on your GPS screen.

1) The micro SD card can become misaligned in the socket under the batteries. Remove the batteries and SD card and carefully re-seat the SD card firmly in the socket.

2) There is a mapset enabled that has a higher draw priority than our maps. Garmin maps such as City Navigator or Inland Lake maps, if enabled, may cover up our topo maps on the GPS screen. Disable City Navigator, Inland Lakes, or other potentially offending mapsets.

3) Check to make sure our maps are enabled in the map setup menu. By default, any newly installed maps are enabled but sometimes they’re accidentally disabled by the user.

If you run into problems or have questions about our products please contact us and we will be glad to help.


My transparent overlay maps aren’t displaying in BaseCamp properly

Transparent maps, such as our Fishing Guide or Hunting District maps do not overlay other maps in BaseCamp due to the way BaseCamp handles transparencies. This is not an issue on our end rather a development issue with Garmin’s program. Don’t worry, the maps, once downloaded and installed, will show beautifully over any topo or base map you have enabled on your GPS screen.

Where can I download BaseCamp or MapSource ?

For our installers to work you will need the Garmin BaseCamp program installed on your computer. It’s free.

You can download BaseCamp for PC and MAC here: http://www.garmin.com/en-US/shop/downloads/basecamp

If you own a MAC you will also need a program called MapConverter which can be found here: http://www8.garmin.com/support/download_details.jsp?id=3897

Follow the instructions carefully. If you still have difficulty installing your mapsets you can contact us and we’ll gladly help with any issues.