diff --git a/opm/output/eclipse/RegionCache.hpp b/opm/output/eclipse/RegionCache.hpp
index a328e3994..c050e44cf 100644
--- a/opm/output/eclipse/RegionCache.hpp
+++ b/opm/output/eclipse/RegionCache.hpp
@@ -36,9 +36,12 @@ namespace out {
         RegionCache(const std::set<std::string>& fip_regions, const FieldPropsManager& fp, const EclipseGrid& grid, const Schedule& schedule);
         const std::vector<std::pair<std::string,size_t>>& connections( const std::string& region_name, int region_id ) const;
 
+        // A well is assigned to the region_id where the first connection is
+        std::vector<std::string> wells(const std::string& region_name, int region_id) const;
     private:
         std::vector<std::pair<std::string,size_t>> connections_empty;
         std::map<std::pair<std::string, int> , std::vector<std::pair<std::string,size_t>>> connection_map;
+        std::map<std::pair<std::string, int>, std::vector<std::string>> well_map;
     };
 }
 }
diff --git a/src/opm/output/eclipse/RegionCache.cpp b/src/opm/output/eclipse/RegionCache.cpp
index d252053c4..3cdfe2eff 100644
--- a/src/opm/output/eclipse/RegionCache.cpp
+++ b/src/opm/output/eclipse/RegionCache.cpp
@@ -36,6 +36,9 @@ RegionCache::RegionCache(const std::set<std::string>& fip_regions, const FieldPr
         const auto& wells = schedule.getWellsatEnd();
         for (const auto& well : wells) {
             const auto& connections = well.getConnections( );
+            if (connections.empty())
+                continue;
+
             for (const auto& c : connections) {
                 if (grid.cellActive(c.getI(), c.getJ(), c.getK())) {
                     size_t active_index = grid.activeIndex(c.getI(), c.getJ(), c.getK());
@@ -45,6 +48,11 @@ RegionCache::RegionCache(const std::set<std::string>& fip_regions, const FieldPr
                     well_index_list.push_back( { well.name() , active_index } );
                 }
             }
+
+            const auto& conn0 = connections[0];
+            auto region_id = fip_region[grid.activeIndex(conn0.global_index())];
+            auto key = std::make_pair(fip_name, region_id);
+            this->well_map[ key ].push_back(well.name());
         }
     }
 }
@@ -59,6 +67,16 @@ RegionCache::RegionCache(const std::set<std::string>& fip_regions, const FieldPr
             return iter->second;
     }
 
+
+    std::vector<std::string> RegionCache::wells(const std::string& region_name, int region_id) const {
+        auto key = std::make_pair(region_name, region_id);
+        const auto iter = this->well_map.find( key );
+        if (iter == this->well_map.end())
+            return {};
+        else
+            return iter->second;
+    }
+
 }
 }
 
diff --git a/tests/summary_deck.DATA b/tests/summary_deck.DATA
index 2e3b6e04f..4d9c1af1e 100644
--- a/tests/summary_deck.DATA
+++ b/tests/summary_deck.DATA
@@ -63,17 +63,17 @@ PERMZ
 REGIONS
 
 FIPNUM
-   100*1
-   100*2
-   100*3
-   100*4
-   100*5
-   100*6
-   100*7
-   100*8
-   100*9
-   100*10 /
-   
+   50*1  50*11
+   50*2  50*12
+   50*3  50*13
+   50*4  50*14
+   50*5  50*15
+   50*6  50*16
+   50*7  50*17
+   50*8  50*18
+   50*9  50*19
+   50*10 50*20
+/ 
 
 SUMMARY
 DATE
@@ -839,7 +839,7 @@ WELSPECS
      'W_2'        'G_1'   2    1  3.33       'OIL'  7* /
      'W_3'        'G_2'   3    1  3.92       'WATER'  7* /
      'W_6'        'G_2'   8    8  3.92       'GAS'  7* /
-     'W_5'        'G_3'   4    1  3.92       'OIL'  7* /
+     'W_5'        'G_3'   6    6  3.92       'OIL'  7* /
 /
 
 -- Completion data.
@@ -850,7 +850,7 @@ COMPDAT
     W_2   0 0  1  1 2*              1*        5  20 0.5 /   -- Active index: 1
     W_2   0 0  2  2 2*              1*        5  10 0.2 /   -- Active index: 101
     W_3   0 0  1  1 2*              1*        2*    0.7 /   -- Active index: 2
-    W_6   0 0  2  2 2*              1*        2*    0.7 /   -- Active index: 2
+    W_6   0 0  1  1 2*              1*        2*    0.7 /   -- Active index: 2
 /
 
 COMPLUMP
@@ -905,7 +905,7 @@ WELSPECS
 /
 
 COMPDAT
-    W_4 1 1 3 3 /
+    W_4 1 1 1 3 /
 /
 
 WPIMULT
diff --git a/tests/test_regionCache.cpp b/tests/test_regionCache.cpp
index e0c0edbbc..a3d328fce 100644
--- a/tests/test_regionCache.cpp
+++ b/tests/test_regionCache.cpp
@@ -23,6 +23,7 @@
 #include <boost/test/unit_test.hpp>
 
 #include <stdexcept>
+#include <unordered_set>
 
 #include <opm/parser/eclipse/Python/Python.hpp>
 #include <opm/parser/eclipse/Deck/Deck.hpp>
@@ -38,6 +39,13 @@ using namespace Opm;
 
 const char* path = "summary_deck.DATA";
 
+bool cmp_list(const std::vector<std::string>& l1, const std::vector<std::string>& l2) {
+    std::unordered_set<std::string> s1(l1.begin(), l1.end());
+    std::unordered_set<std::string> s2(l2.begin(), l2.end());
+    return s1 == s2;
+}
+
+
 
 BOOST_AUTO_TEST_CASE(create) {
     auto python = std::make_shared<Python>();
@@ -54,11 +62,17 @@ BOOST_AUTO_TEST_CASE(create) {
 
     {
         const auto& top_layer = rc.connections(  "FIPNUM", 1 );
-        BOOST_CHECK_EQUAL( top_layer.size() , 3U );
+        BOOST_CHECK_EQUAL( top_layer.size() , 4U );
         {
             auto pair = top_layer[0];
             BOOST_CHECK_EQUAL( pair.first , "W_1");
             BOOST_CHECK_EQUAL( pair.second , grid.activeIndex( 0,0,0));
         }
     }
+
+    BOOST_CHECK( rc.wells("FIPXYZ", 100).empty() );
+    BOOST_CHECK( rc.wells("FIPXYZ", 1).empty() );
+    BOOST_CHECK( rc.wells("FIPNUM", 100).empty() );
+    BOOST_CHECK( cmp_list(rc.wells("FIPNUM", 1),  {"W_1", "W_2", "W_3", "W_4"}));
+    BOOST_CHECK( cmp_list(rc.wells("FIPNUM", 11), {"W_6"}));
 }