diff --git a/src/main/java/com/conveyal/gtfs/error/NewGTFSErrorType.java b/src/main/java/com/conveyal/gtfs/error/NewGTFSErrorType.java
index 49f44fa3f..477c034dc 100644
--- a/src/main/java/com/conveyal/gtfs/error/NewGTFSErrorType.java
+++ b/src/main/java/com/conveyal/gtfs/error/NewGTFSErrorType.java
@@ -47,6 +47,7 @@ public enum NewGTFSErrorType {
     ROUTE_LONG_NAME_CONTAINS_SHORT_NAME(Priority.LOW, "The long name of a route should complement the short name, not include it."),
     ROUTE_SHORT_AND_LONG_NAME_MISSING(Priority.MEDIUM, "A route has neither a long nor a short name."),
     ROUTE_SHORT_NAME_TOO_LONG(Priority.MEDIUM, "The short name of a route is too long for display in standard GTFS consumer applications."),
+    ROUTE_TYPE_INVALID(Priority.MEDIUM, "The route type is not valid."),
     ROUTE_UNUSED(Priority.MEDIUM, "This route is defined but has no trips."),
     SERVICE_NEVER_ACTIVE(Priority.MEDIUM, "A service code was defined, but is never active on any date."),
     SERVICE_UNUSED(Priority.MEDIUM, "A service code was defined, but is never referenced by any trips."),
diff --git a/src/main/java/com/conveyal/gtfs/validator/RouteTypeValidator.java b/src/main/java/com/conveyal/gtfs/validator/RouteTypeValidator.java
new file mode 100644
index 000000000..740694297
--- /dev/null
+++ b/src/main/java/com/conveyal/gtfs/validator/RouteTypeValidator.java
@@ -0,0 +1,56 @@
+package com.conveyal.gtfs.validator;
+
+import com.conveyal.gtfs.error.SQLErrorStorage;
+import com.conveyal.gtfs.loader.Feed;
+import com.conveyal.gtfs.model.Route;
+
+import java.util.List;
+
+import static com.conveyal.gtfs.error.NewGTFSErrorType.ROUTE_TYPE_INVALID;
+
+/**
+ * Validates route types based on a configured list of values.
+ */
+public class RouteTypeValidator extends FeedValidator {
+    private final List<Integer> configuredRouteTypes;
+
+    /**
+     * Constructor used for tests in the same package.
+     */
+    RouteTypeValidator(List<Integer> routeTypes) {
+        this(null, null, routeTypes);
+    }
+
+    /**
+     * Constructor for building a route type validator given a set of valid route types.
+     */
+    public RouteTypeValidator(Feed feed, SQLErrorStorage errorStorage, List<Integer> routeTypes) {
+        super(feed, errorStorage);
+        this.configuredRouteTypes = routeTypes;
+    }
+
+    @Override
+    public void validate() {
+        feed.routes.forEach(this::validateRouteType);
+    }
+
+    /**
+     * @return true if routeType is one of the configured route types, false otherwise.
+     */
+    public boolean isRouteTypeValid(int routeType) {
+        return configuredRouteTypes.contains(routeType);
+    }
+
+    /**
+     * Checks that the route type is valid, reports a validation error if not.
+     * @param route The containing GTFS route.
+     * @return true if the route type for the given route is valid, false otherwise.
+     */
+    public boolean validateRouteType(Route route) {
+        if (!isRouteTypeValid(route.route_type)) {
+            if (errorStorage != null) registerError(route, ROUTE_TYPE_INVALID, route.route_type);
+            return false;
+        }
+        return true;
+    }
+}
diff --git a/src/test/java/com/conveyal/gtfs/validator/RouteTypeValidatorTest.java b/src/test/java/com/conveyal/gtfs/validator/RouteTypeValidatorTest.java
new file mode 100644
index 000000000..4303f3dc6
--- /dev/null
+++ b/src/test/java/com/conveyal/gtfs/validator/RouteTypeValidatorTest.java
@@ -0,0 +1,21 @@
+package com.conveyal.gtfs.validator;
+
+import com.google.common.collect.Lists;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class RouteTypeValidatorTest {
+    private static final List<Integer> TEST_ROUTE_TYPES = Lists.newArrayList(3, 101);
+    private static final RouteTypeValidator ROUTE_TYPE_VALIDATOR = new RouteTypeValidator(TEST_ROUTE_TYPES);
+
+    @Test
+    void validateRouteType() {
+        assertTrue(ROUTE_TYPE_VALIDATOR.isRouteTypeValid(3)); // Bus
+        assertFalse(ROUTE_TYPE_VALIDATOR.isRouteTypeValid(36)); // Invalid
+        assertTrue(ROUTE_TYPE_VALIDATOR.isRouteTypeValid(101)); // High Speed Rail
+    }
+}