diff --git a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
index 901520ed455..ff05db300f1 100644
--- a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
+++ b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
@@ -410,6 +410,14 @@ interface BusBreakerView {
          */
         Stream<Bus> getBusStream();
 
+        /**
+         * Get the bus count.
+         * <p>
+         * Depends on the working variant.
+         * @see VariantManager
+         */
+        int getBusCount();
+
         /**
          * Get all switches
          */
diff --git a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/VoltageLevel.java b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/VoltageLevel.java
index 9f84cb39ddf..faba9b21581 100644
--- a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/VoltageLevel.java
+++ b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/VoltageLevel.java
@@ -707,6 +707,15 @@ interface SwitchAdder extends IdentifiableAdder<Switch, SwitchAdder> {
          */
         Stream<Bus> getBusStream();
 
+        /**
+         * Get the bus count.
+         * <p>
+         * Depends on the working variant if topology kind is NODE_BREAKER.
+         *
+         * @see VariantManager
+         */
+        int getBusCount();
+
         /**
          * Get a bus.
          * <p>
diff --git a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/BusBreakerVoltageLevel.java b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/BusBreakerVoltageLevel.java
index 789ac17090f..0af6f7cc03f 100644
--- a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/BusBreakerVoltageLevel.java
+++ b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/BusBreakerVoltageLevel.java
@@ -599,6 +599,11 @@ public Stream<Bus> getBusStream() {
             return graph.getVertexObjectStream().map(Function.identity());
         }
 
+        @Override
+        public int getBusCount() {
+            return graph.getVertexCount();
+        }
+
         @Override
         public ConfiguredBus getBus(String id) {
             return BusBreakerVoltageLevel.this.getBus(id, false);
diff --git a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java
index f8295e00fe4..4d06cb1d6a6 100644
--- a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java
+++ b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java
@@ -66,6 +66,11 @@ public Stream<Bus> getBusStream() {
             return getVoltageLevelStream().flatMap(vl -> vl.getBusBreakerView().getBusStream());
         }
 
+        @Override
+        public int getBusCount() {
+            return getVoltageLevelStream().mapToInt(vl -> vl.getBusBreakerView().getBusCount()).sum();
+        }
+
         @Override
         public Iterable<Switch> getSwitches() {
             return FluentIterable.from(getVoltageLevels())
diff --git a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NodeBreakerVoltageLevel.java b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NodeBreakerVoltageLevel.java
index 7722bd81791..6969fa9cd2c 100644
--- a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NodeBreakerVoltageLevel.java
+++ b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NodeBreakerVoltageLevel.java
@@ -229,6 +229,10 @@ private Collection<CalculatedBus> getBuses() {
             return id2bus.values();
         }
 
+        private int getBusCount() {
+            return id2bus.size();
+        }
+
         private CalculatedBus getBus(int node) {
             return node2bus[node];
         }
@@ -321,6 +325,11 @@ Collection<CalculatedBus> getBuses() {
             return busCache.getBuses();
         }
 
+        int getBusCount() {
+            updateCache();
+            return busCache.getBusCount();
+        }
+
         CalculatedBus getBus(int node) {
             updateCache();
             return busCache.getBus(node);
@@ -985,6 +994,11 @@ public Stream<Bus> getBusStream() {
             return variants.get().calculatedBusBreakerTopology.getBuses().stream().map(Function.identity());
         }
 
+        @Override
+        public int getBusCount() {
+            return variants.get().calculatedBusBreakerTopology.getBusCount();
+        }
+
         @Override
         public CalculatedBus getBus(String id) {
             return variants.get().calculatedBusBreakerTopology.getBus(id, false);
diff --git a/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractNetworkTest.java b/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractNetworkTest.java
index 5bd01626418..312bd782297 100644
--- a/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractNetworkTest.java
+++ b/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractNetworkTest.java
@@ -58,6 +58,7 @@ public void testNetwork1() {
         assertEquals(1, Iterables.size(network.getSubstations()));
         assertEquals(1, Iterables.size(network.getSubstations(Country.FR, "TSO1", REGION1)));
         assertEquals(1, network.getSubstationCount());
+        assertEquals(2, network.getBusBreakerView().getBusCount());
 
         Substation substation1 = network.getSubstation(SUBSTATION12);
         assertNotNull(substation1);
@@ -156,6 +157,7 @@ public void testNetwork1() {
         assertEquals(300.0, rcc1.getMinQ(500), 0.0);
 
         assertEquals(2, Iterables.size(voltageLevel1.getBusBreakerView().getBuses()));
+        assertEquals(2, voltageLevel1.getBusBreakerView().getBusCount());
         Bus busCalc1 = voltageLevel1BusbarSection1.getTerminal().getBusBreakerView().getBus();
         Bus busCalc2 = voltageLevel1BusbarSection2.getTerminal().getBusBreakerView().getBus();
         assertSame(busCalc1, load1.getTerminal().getBusBreakerView().getBus());
@@ -268,6 +270,7 @@ public void testNetworkWithBattery() {
         assertEquals(2, network.getVoltageLevelCount());
         assertEquals(2, Iterables.size(network.getBatteries()));
         assertEquals(2, network.getBatteryCount());
+        assertEquals(2, network.getBusBreakerView().getBusCount());
 
         // Substation A
         Substation substation1 = network.getSubstation("P1");
@@ -284,6 +287,7 @@ public void testNetworkWithBattery() {
         assertEquals(400.0, voltageLevel1.getNominalV(), 0.0);
         assertSame(substation1, voltageLevel1.getSubstation().orElse(null));
         assertSame(TopologyKind.BUS_BREAKER, voltageLevel1.getTopologyKind());
+        assertEquals(1, voltageLevel1.getBusBreakerView().getBusCount());
 
         Bus bus1 = voltageLevel1.getBusBreakerView().getBus("NGEN");
         assertEquals(3, bus1.getConnectedTerminalCount());