diff --git a/api/api-v1/src/main/kotlin/org/vibeerp/api/v1/ext/inventory/InventoryApi.kt b/api/api-v1/src/main/kotlin/org/vibeerp/api/v1/ext/inventory/InventoryApi.kt
index 823033a..41168a2 100644
--- a/api/api-v1/src/main/kotlin/org/vibeerp/api/v1/ext/inventory/InventoryApi.kt
+++ b/api/api-v1/src/main/kotlin/org/vibeerp/api/v1/ext/inventory/InventoryApi.kt
@@ -40,6 +40,25 @@ import java.math.BigDecimal
 interface InventoryApi {
 
     /**
+     * Look up an inventory location by its stable business code.
+     * Returns `null` when no location with that code exists.
+     *
+     * Cross-PBC callers use this as a pre-flight validation before
+     * committing to an operation that needs a location: for example,
+     * pbc-warehousing's `StockTransferService.create` uses it to
+     * reject an unknown `fromLocationCode` at document-creation time
+     * rather than waiting until `confirm()` rolls back a partial
+     * ledger write. Same shape as
+     * [org.vibeerp.api.v1.ext.catalog.CatalogApi.findItemByCode] — a
+     * lookup-by-code returning a lightweight ref or null.
+     *
+     * Only the code is returned (plus a few common descriptive
+     * fields); callers that need the full location record should go
+     * through the inventory REST API with their own token.
+     */
+    fun findLocationByCode(locationCode: String): LocationRef?
+
+    /**
      * Look up the on-hand stock balance for [itemCode] at
      * [locationCode]. Returns `null` when no balance row exists for
      * that combination — the framework treats "no row" as "no stock",
@@ -131,3 +150,27 @@ data class StockBalanceRef(
     val locationCode: String,
     val quantity: BigDecimal,
 )
+
+/**
+ * Minimal, safe-to-publish view of an inventory location.
+ *
+ * Returned by [InventoryApi.findLocationByCode]. Carries the stable
+ * business code, the display name, and the active flag. Fields that
+ * are not here are deliberately not part of the cross-PBC contract:
+ * the underlying id, the `ext` JSONB, the audit columns. A cross-PBC
+ * caller that needs richer location data should hit the inventory
+ * REST API directly with their own token.
+ *
+ * The `type` field is a free-form String, not an enum, because
+ * pbc-inventory has historically grown new location types
+ * (WAREHOUSE, SHOP, VIRTUAL, IN_TRANSIT, ...) at roughly one per
+ * quarter; a String here decouples the cross-PBC surface from that
+ * churn. Callers that want to switch on it do so at their own risk.
+ */
+data class LocationRef(
+    val id: Id<LocationRef>,
+    val code: String,
+    val name: String,
+    val type: String,
+    val active: Boolean,
+)
diff --git a/pbc/pbc-inventory/src/main/kotlin/org/vibeerp/pbc/inventory/ext/InventoryApiAdapter.kt b/pbc/pbc-inventory/src/main/kotlin/org/vibeerp/pbc/inventory/ext/InventoryApiAdapter.kt
index c22ab33..0c09374 100644
--- a/pbc/pbc-inventory/src/main/kotlin/org/vibeerp/pbc/inventory/ext/InventoryApiAdapter.kt
+++ b/pbc/pbc-inventory/src/main/kotlin/org/vibeerp/pbc/inventory/ext/InventoryApiAdapter.kt
@@ -4,9 +4,11 @@ import org.springframework.stereotype.Component
 import org.springframework.transaction.annotation.Transactional
 import org.vibeerp.api.v1.core.Id
 import org.vibeerp.api.v1.ext.inventory.InventoryApi
+import org.vibeerp.api.v1.ext.inventory.LocationRef
 import org.vibeerp.api.v1.ext.inventory.StockBalanceRef
 import org.vibeerp.pbc.inventory.application.RecordMovementCommand
 import org.vibeerp.pbc.inventory.application.StockMovementService
+import org.vibeerp.pbc.inventory.domain.Location
 import org.vibeerp.pbc.inventory.domain.MovementReason
 import org.vibeerp.pbc.inventory.domain.StockBalance
 import org.vibeerp.pbc.inventory.infrastructure.LocationJpaRepository
@@ -48,6 +50,11 @@ class InventoryApiAdapter(
     private val stockMovementService: StockMovementService,
 ) : InventoryApi {
 
+    override fun findLocationByCode(locationCode: String): LocationRef? {
+        val location = locations.findByCode(locationCode) ?: return null
+        return location.toRef()
+    }
+
     override fun findStockBalance(itemCode: String, locationCode: String): StockBalanceRef? {
         val location = locations.findByCode(locationCode) ?: return null
         val balance = balances.findByItemCodeAndLocationId(itemCode, location.id) ?: return null
@@ -108,4 +115,12 @@ class InventoryApiAdapter(
         locationCode = locationCode,
         quantity = this.quantity,
     )
+
+    private fun Location.toRef(): LocationRef = LocationRef(
+        id = Id<LocationRef>(this.id),
+        code = this.code,
+        name = this.name,
+        type = this.type.name,
+        active = this.active,
+    )
 }
diff --git a/pbc/pbc-warehousing/src/main/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferService.kt b/pbc/pbc-warehousing/src/main/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferService.kt
index fc88755..045d782 100644
--- a/pbc/pbc-warehousing/src/main/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferService.kt
+++ b/pbc/pbc-warehousing/src/main/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferService.kt
@@ -81,6 +81,26 @@ class StockTransferService(
             "stock transfer '${command.code}' must have at least one line"
         }
 
+        // Validate both locations exist via the inventory facade. Doing
+        // this at create time (not just at confirm time) means the
+        // operator gets immediate feedback on a typo instead of
+        // discovering it only when the confirm rolls back. Same
+        // pattern: ItemCode is validated at create via CatalogApi too.
+        val fromLocation = inventoryApi.findLocationByCode(command.fromLocationCode)
+            ?: throw IllegalArgumentException(
+                "from location code '${command.fromLocationCode}' is not in the inventory directory",
+            )
+        val toLocation = inventoryApi.findLocationByCode(command.toLocationCode)
+            ?: throw IllegalArgumentException(
+                "to location code '${command.toLocationCode}' is not in the inventory directory",
+            )
+        require(fromLocation.active) {
+            "from location '${command.fromLocationCode}' is deactivated and cannot be transfer source"
+        }
+        require(toLocation.active) {
+            "to location '${command.toLocationCode}' is deactivated and cannot be transfer destination"
+        }
+
         val seenLineNos = HashSet<Int>(command.lines.size)
         for (line in command.lines) {
             require(line.lineNo > 0) {
diff --git a/pbc/pbc-warehousing/src/test/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferServiceTest.kt b/pbc/pbc-warehousing/src/test/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferServiceTest.kt
index a167f66..b9f5190 100644
--- a/pbc/pbc-warehousing/src/test/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferServiceTest.kt
+++ b/pbc/pbc-warehousing/src/test/kotlin/org/vibeerp/pbc/warehousing/application/StockTransferServiceTest.kt
@@ -16,6 +16,7 @@ import org.vibeerp.api.v1.core.Id
 import org.vibeerp.api.v1.ext.catalog.CatalogApi
 import org.vibeerp.api.v1.ext.catalog.ItemRef
 import org.vibeerp.api.v1.ext.inventory.InventoryApi
+import org.vibeerp.api.v1.ext.inventory.LocationRef
 import org.vibeerp.api.v1.ext.inventory.StockBalanceRef
 import org.vibeerp.pbc.warehousing.domain.StockTransfer
 import org.vibeerp.pbc.warehousing.domain.StockTransferStatus
@@ -42,6 +43,16 @@ class StockTransferServiceTest {
         )
     }
 
+    private fun stubLocation(code: String, active: Boolean = true) {
+        every { inventory.findLocationByCode(code) } returns LocationRef(
+            id = Id(UUID.randomUUID()),
+            code = code,
+            name = "$code name",
+            type = "WAREHOUSE",
+            active = active,
+        )
+    }
+
     private fun cmd(
         code: String = "TR-001",
         from: String = "WH-A",
@@ -60,6 +71,8 @@ class StockTransferServiceTest {
     @Test
     fun `create persists a DRAFT transfer when everything validates`() {
         every { transfers.existsByCode("TR-001") } returns false
+        stubLocation("WH-A")
+        stubLocation("WH-B")
         stubItemExists("ITEM-1")
         stubItemExists("ITEM-2")
         every { transfers.save(any<StockTransfer>()) } answers { firstArg() }
@@ -105,6 +118,8 @@ class StockTransferServiceTest {
     @Test
     fun `create rejects duplicate line numbers`() {
         every { transfers.existsByCode(any()) } returns false
+        stubLocation("WH-A")
+        stubLocation("WH-B")
         stubItemExists("X")
 
         assertFailure {
@@ -124,6 +139,8 @@ class StockTransferServiceTest {
     @Test
     fun `create rejects non-positive quantities`() {
         every { transfers.existsByCode(any()) } returns false
+        stubLocation("WH-A")
+        stubLocation("WH-B")
         stubItemExists("X")
 
         assertFailure {
@@ -137,6 +154,8 @@ class StockTransferServiceTest {
     @Test
     fun `create rejects unknown items via CatalogApi`() {
         every { transfers.existsByCode(any()) } returns false
+        stubLocation("WH-A")
+        stubLocation("WH-B")
         every { catalog.findItemByCode("GHOST") } returns null
 
         assertFailure {
@@ -148,6 +167,37 @@ class StockTransferServiceTest {
     }
 
     @Test
+    fun `create rejects unknown from location via InventoryApi`() {
+        every { transfers.existsByCode(any()) } returns false
+        every { inventory.findLocationByCode("WH-A") } returns null
+
+        assertFailure { service.create(cmd(from = "WH-A", to = "WH-B")) }
+            .isInstanceOf(IllegalArgumentException::class)
+            .hasMessage("from location code 'WH-A' is not in the inventory directory")
+    }
+
+    @Test
+    fun `create rejects unknown to location via InventoryApi`() {
+        every { transfers.existsByCode(any()) } returns false
+        stubLocation("WH-A")
+        every { inventory.findLocationByCode("WH-B") } returns null
+
+        assertFailure { service.create(cmd(from = "WH-A", to = "WH-B")) }
+            .isInstanceOf(IllegalArgumentException::class)
+            .hasMessage("to location code 'WH-B' is not in the inventory directory")
+    }
+
+    @Test
+    fun `create rejects a deactivated from location`() {
+        every { transfers.existsByCode(any()) } returns false
+        stubLocation("WH-A", active = false)
+        stubLocation("WH-B")
+
+        assertFailure { service.create(cmd(from = "WH-A", to = "WH-B")) }
+            .isInstanceOf(IllegalArgumentException::class)
+    }
+
+    @Test
     fun `confirm writes an atomic TRANSFER_OUT + TRANSFER_IN pair per line`() {
         val id = UUID.randomUUID()
         val transfer = StockTransfer(