diff --git a/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetHmppsIdService.kt b/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetHmppsIdService.kt
index b00eee3b4..e89814e78 100644
--- a/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetHmppsIdService.kt
+++ b/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetHmppsIdService.kt
@@ -11,10 +11,16 @@ class GetHmppsIdService(
   @Autowired val getPersonService: GetPersonService,
 ) {
   fun execute(hmppsId: String): Response<HmppsId?> {
-    val personResponse = getPersonService.execute(hmppsId = hmppsId)
+    val personResponse = getPersonService.execute(hmppsId)
+
+    val hmppsIdToReturn =
+      personResponse.data?.hmppsId ?: run {
+        // Attempt to look up the person in NOMIS if not found in the probation offender search
+        getPersonService.getPersonFromNomis(hmppsId).data?.prisonerNumber
+      }
 
     return Response(
-      data = HmppsId(hmppsId = personResponse.data?.hmppsId),
+      data = HmppsId(hmppsIdToReturn),
       errors = personResponse.errors,
     )
   }
diff --git a/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetPersonService.kt b/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetPersonService.kt
index cd584f58a..108c1571e 100644
--- a/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetPersonService.kt
+++ b/src/main/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/services/GetPersonService.kt
@@ -103,4 +103,6 @@ class GetPersonService(
       errors = (prisonResponse?.errors ?: emptyList()) + probationResponse.errors,
     )
   }
+
+  fun getPersonFromNomis(nomisNumber: String) = prisonerOffenderSearchGateway.getPrisonOffender(nomisNumber)
 }
diff --git a/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/HmppsIdIntegrationTest.kt b/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/HmppsIdIntegrationTest.kt
index fb282d229..a0244d749 100644
--- a/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/HmppsIdIntegrationTest.kt
+++ b/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/HmppsIdIntegrationTest.kt
@@ -44,6 +44,19 @@ class HmppsIdIntegrationTest : IntegrationTestBase() {
       )
   }
 
+  @Test
+  fun `gets the nomis Id for a HMPPSID where the id is a NOMIS id AND is not in delius`() {
+    callApi("/v1/hmpps/id/$nomsIdNotInDelius/nomis-number")
+      .andExpect(status().isOk)
+      .andExpect(
+        content().json(
+          """
+        {"data":{"nomisNumber":"A1234AA"}}
+      """,
+        ),
+      )
+  }
+
   @Test
   fun `gets the nomis Id for a HMPPSID where the id is invalid`() {
     callApi("/v1/hmpps/id/invalidId/nomis-number")
diff --git a/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/IntegrationTestBase.kt b/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/IntegrationTestBase.kt
index 60e908702..93349203a 100644
--- a/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/IntegrationTestBase.kt
+++ b/src/test/kotlin/uk/gov/justice/digital/hmpps/hmppsintegrationapi/integration/IntegrationTestBase.kt
@@ -28,6 +28,7 @@ abstract class IntegrationTestBase {
   final val pnc = URLEncoder.encode("2004/13116M", StandardCharsets.UTF_8)
   final val nomsId = "G2996UX"
   final val crn = "AB123123"
+  final val nomsIdNotInDelius = "A1234AA"
 
   companion object {
     private val hmppsAuthMockServer = HmppsAuthMockServer()