A feature layer is a grouping of similar geographic features, for example, buildings, parcels, cities, roads, and earthquake epicenters. Features can be points, lines, or polygons (areas). Feature layers are most appropriate for visualizing data on top of your basemaps. You can set properties for feature layers—such as style, transparency, visible range, refresh interval, and labels—that control how the layer appears in the map. Using a feature layer, you can view, edit, analyze, and execute queries against features and their attributes.
Each type of feature layer meets a different need and, therefore, has slightly different functionality. For a comparison of functionality available with each type of feature layer, see Feature layer functionality.
Hosted feature layers
Hosted feature layers are feature services whose feature data is hosted by, or stored in, one of two different system-maintained data stores.
You can think of the layer, service, and its data as a single entity. When you create a hosted feature layer, the data is copied into one of the data stores. When the owner of the hosted feature layer or an administrator deletes a hosted feature layer, the service and data are also deleted.
The functionality available varies slightly depending on the data store the hosted feature layer accesses. You can identify the two types of layers based on the layer icon.
Hosted feature layer
Hosted feature layers are created when you
publish a feature layer to ArcGIS Enterprise from ArcGIS Pro or from files in the portal.
ArcGIS Server feature layers
If you have access to feature services running on a stand-alone or federated ArcGIS Server site, you can still use these ArcGIS Server feature services as layers in your portal. These layers are similar to hosted feature layers with the following differences:
- The data is not copied into a system-maintained data store; it stays in the data source you registered with the ArcGIS Server site.
- When you delete the ArcGIS Server feature layer, the data is not deleted.
- Much of the configuration for ArcGIS Server feature layers is performed in ArcGIS Server Manager, not the portal.
- Functionality available in the portal is different for ArcGIS Server feature layers than for hosted feature layers.
Many of these differences guard against unwanted changes being made to the data stored in the folders and databases you registered with your ArcGIS Server site, as this data is often your system of record and is likely accessed directly by other applications. However, the hosted feature layer data is managed through the portal and not directly accessed by other applications.
When you publish a feature layer (feature service) to a federated ArcGIS Server site, it is automatically added as a feature layer to your portal. If you want to work with a feature service from a stand-alone ArcGIS Server site, you can add it to your portal from My Content. This allows you to reference the REST endpoint (URL) of the service and use the layer in your maps and apps while leaving the data stored in the data sources you registered with your ArcGIS Server site. You can also add ArcGIS Server feature layers to Map Viewer or add them to Map Viewer Classic.
Layers in an ArcGIS Server map or feature service
You can add individual layers in a map service or feature service as an item or to a map in Map Viewer or Map Viewer Classic. This allows you to use a single layer in the service in a map or app instead of having to use all layers in the service.
For example, if you have access to an ArcGIS Server map service that contains a roads layer, a buildings layer, and a railroads layer, but you only need to access the roads, you can add the roads layer as an item (recommended if you need to provide credentials to access the service) or directly to your map. To do this, you need to copy the roads layer's URL from the REST endpoint of the map service. The URL for a map service's REST endpoint is in the format https://<server>.<domain>/server/rest/services/<service_name>/MapServer. A link for each layer in the service is listed in the Layers section of this page. Click the link for the layer you want to use. Copy the URL of the page that opens to obtain the layer's URL.
Note:
Feature layers created from a layer in a map service are always read-only; you cannot enable editing on them.
Feature collections
Items such as CSV files, shapefiles, and map notes can be added to a map as feature collections. A feature collection is a type of feature layer. Any feature collection you add can be saved as part of the map. Doing so saves the feature collection data as part of the map. Any changes you make to the feature collection—for example, by editing data—are only reflected in the map. The changes are not applied to the original CSV file, shapefile, or map note from which the feature collection was derived.
You can also save a feature collection as its own item by clicking Save Layer in the layer properties menu. The item will appear as a new feature collection item in My Content and can be shared with others and added to multiple maps. When you save a feature collection as its own item, the data is retained with the feature collection item and not stored as part of the map. Any changes you make to the feature collection item, such as modifying its data, are saved once you click Save Layer. If the feature collection item is used in other maps, the changes will be reflected there as well. If the feature collection item is deleted from My Content, it will no longer be available to others.
Map notes
You can create features on your map by adding a map notes layer. A map notes layer is a type of feature collection. With a map notes layer, you use features to symbolize something you want to show on your map, such as public access points, hiking trails, or fire perimeters. You can also add descriptive information that appears in pop-ups when the feature is clicked.
By default, the features in a map notes layer are saved with the map so that only you, the map author, can edit and save them. You can also choose to save the layer as a feature collection item in your content, which allows you to edit its item details and share it with others. Map notes layers are useful for displaying information such as events happening within a community or an inventory of oil production facilities. This is a good way to add a small number of features to a map, for example, the swimming pools managed by your city's parks and recreation department. It's also a way to create feature layers if you don't have portal publishing privileges.
Route layers
You can use Map Viewer Classic to get directions and create a route layer in your map. Route layers are a type of feature collection that contain four sublayers—stops, direction events, directions, and route info—each with its own properties, such as pop-ups and labels, that you can configure as desired. From Map Viewer Classic, you can save the route layer as an item in My Content and use it in other maps. Once the route layer is saved as an item, you can share it with others.
Streaming feature layers
Streaming feature layers are feature layers created from an ArcGIS GeoEvent Server stream service. They are useful for visualizing real-time data feeds that have high volumes of data or that have data that changes at unknown intervals. For example, a fleet of vehicles might be transmitting their location, and the current location of the vehicles needs to be continuously monitored. When you add a streaming feature layer to Map Viewer Classic, you can use streaming controls to filter the data that the service sends to the layer. Streaming feature layers can be identified by their icon 
in the content page.
Streaming feature layers connect to an ArcGIS Server stream service using HTML5 WebSockets. Most modern browsers support WebSockets.
Feature layer functionality
The following sections list how to create each type of feature layer and compare functionality available with each type in Map Viewer Classic, Map Viewer, Scene Viewer, and item details.
Publishing methods
The following list describes how you create each type of feature layer in an ArcGIS Enterprise portal:
- Hosted feature layer—Add an item to the portal and publish, publish from ArcGIS Pro, or create from a template. See Publish hosted feature layers for more information.
- ArcGIS Server feature layer—Publish from ArcGIS Pro to a federated ArcGIS Server site, publish from ArcGIS Pro to a stand-alone ArcGIS Server site and add the service to your organization, or publish from data store items in the portal website.
- Feature collection—Add a CSV file, shapefile, or map notes to Map Viewer Classic (formerly known as Map Viewer) and save the layer.
Map Viewer Classic
All feature layer items in your portal can be added to Map Viewer Classic (formerly known as Map Viewer), but the available functionality may differ slightly. The following table compares feature layer functionality in Map Viewer Classic:
| Functionality | Hosted feature layer | ArcGIS Server feature layer | Feature collection |
|---|---|---|---|
Edit (if editing is enabled on the layer) | Yes | Yes | Not applicable; editing cannot be enabled on feature collections |
Yes | Yes | No | |
Yes | Yes | Yes | |
Define labels | Yes | Yes | Yes, but not supported for map notes |
Yes | Yes | No | |
Yes | Yes | Yes | |
Apply filters | No | ||
Yes | Yes | No | |
Yes | Yes | Yes | |
Calculate fields in the attribute table | Yes | No | No |
Add fields to and delete fields from the attribute table | Yes | No | No |
Display features aggregated in bins | No | No | No |
Map Viewer
At this time, you can add a subset of feature layer types to Map Viewer. The available functionality for each layer type may differ slightly. The following table compares feature layer functionality in Map Viewer:
| Functionality | Hosted feature layer | ArcGIS Server feature layer |
|---|---|---|
Edit (if editing is enabled on the layer) | Yes | Yes |
Add to map with full editing control | No | No |
Yes | Yes | |
Define labels | Yes | Yes |
Set refresh interval | No | No |
Yes | Yes | |
Yes | Yes | |
Copy and save as a new layer | No | No |
Use standard feature analysis tools and GeoAnalytics feature analysis tools | No | No |
Calculate fields in the attribute table | Yes | No |
Add fields to and delete fields from the attribute table | Yes | No |
Display features aggregated in bins | No | No |
Scene Viewer
You can add the following types of feature layers to Scene Viewer:
- Hosted feature layer
- ArcGIS Server feature layer
Each layer can contain an unlimited number of features.
Item details
Many of the settings and details you configure for feature layers are the same for all feature layers and for portal items in general, such as setting tags and categories, setting a summary and description, enabling delete protection, and setting an extent. Settings and details that are different across feature layers are listed in the following table:
| Functionality | Hosted feature layer | ArcGIS Server feature layer | Feature collection |
|---|---|---|---|
Publish other layers from | Yes | No | Yes, a hosted feature layer |
Create views from | Yes | You cannot create views from the feature layer in the portal, but the equivalent workflow is to publish multiple feature layers from the same data in an ArcGIS Desktop app or ArcGIS Pro. | No |
Define view areas on the Visualization tab | Yes | Not applicable | Not applicable |
Export data from | Yes | No | No |
Add and view metadata | Yes | Yes | Yes |
Yes | You cannot enable attachments from the portal. However, you can enable attachments on the source data before publishing the feature layer. | No | |
Yes | You cannot overwrite from the portal. However, you can overwrite from ArcGIS Pro. | No | |
Append data | Yes You can also use the Append geoprocessing tool in ArcGIS Pro. | You cannot append from the portal. However, because the data resides in your ArcGIS Server site's registered data store, you can append to the source data. | No |
Calculate field contents on the Data tab | Yes | No | No |
Add fields and delete fields on the Data tab | Yes | No | No |
Yes | No; you can view existing lists and ranges but not add or delete them on the Data tab. | No | |
Yes | No | No | |
Edit nonspatial field values on the Data tab | Yes | Yes | No |
Alter field properties including display name (title), description, field value type, and whether edits are allowed for a field | Yes | No | Can edit display name, description, and field value type but not the other field properties. |
Apply filters on the Visualization tab | Yes | Yes | No |
Yes | You cannot enable editing or modify editing settings from the portal. Configure editing settings when you publish the feature layer or modify settings in ArcGIS Server Manager after publishing. | No | |
Yes | You cannot enable sync from the portal. This is set when publishing, or you can modify the setting in ArcGIS Server Manager after publishing. | No | |
Yes | You cannot enable editor tracking in the portal. However, you can enable editor tracking on the source data from ArcGIS Pro. | No | |
Control whether editable layers can be shared with everyone (public) | Yes | No | No |
Update details, data, and visualization configuration for individual sublayers | Yes | Yes | No |