diff --git a/src/helpers/logging/logger.js b/src/helpers/logging/logger.js
index 7e7e63f..e71e12f 100644
--- a/src/helpers/logging/logger.js
+++ b/src/helpers/logging/logger.js
@@ -5,6 +5,10 @@ import { loggerOptions } from '~/src/helpers/logging/logger-options.js'
 /**
  * Create a logger instance.
  */
-export function createLogger() {
+function createPinoLogger() {
   return pino(loggerOptions)
 }
+
+// Singleton logger instance - pino adds 'exit' listeners to process,
+// so we reuse a single instance to avoid MaxListenersExceededWarning
+export const logger = createPinoLogger()
diff --git a/src/index.js b/src/index.js
index 0bfa919..156aa74 100644
--- a/src/index.js
+++ b/src/index.js
@@ -2,9 +2,7 @@ import { chdir } from 'node:process'
 
 import { getErrorMessage } from '@defra/forms-model'
 
-import { createLogger } from '~/src/helpers/logging/logger.js'
-
-const logger = createLogger()
+import { logger } from '~/src/helpers/logging/logger.js'
 
 // Move working directory to build output
 chdir(import.meta.dirname)
diff --git a/src/messaging/event.js b/src/messaging/event.js
index eb2ceb9..080f2a6 100644
--- a/src/messaging/event.js
+++ b/src/messaging/event.js
@@ -5,7 +5,7 @@ import {
 } from '@aws-sdk/client-sqs'
 
 import { config } from '~/src/config/index.js'
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import { sqsClient } from '~/src/messaging/sqs.js'
 
 export const receiveMessageTimeout = config.get('receiveMessageTimeout')
@@ -15,8 +15,6 @@ const deadLetterQueueArn = config.get('sqsEventsDlqArn')
 const maxNumberOfMessages = config.get('maxNumberOfMessages')
 const visibilityTimeout = config.get('visibilityTimeout')
 
-const logger = createLogger()
-
 /**
  * @type {ReceiveMessageCommandInput}
  */
diff --git a/src/messaging/event.test.js b/src/messaging/event.test.js
index d84580c..fc47670 100644
--- a/src/messaging/event.test.js
+++ b/src/messaging/event.test.js
@@ -15,7 +15,13 @@ import {
   redriveDlqMessages
 } from '~/src/messaging/event.js'
 
-jest.mock('~/src/helpers/logging/logger.js')
+jest.mock('~/src/helpers/logging/logger.js', () => ({
+  logger: {
+    info: jest.fn(),
+    error: jest.fn(),
+    debug: jest.fn()
+  }
+}))
 
 describe('event', () => {
   const snsMock = mockClient(SQSClient)
diff --git a/src/plugins/auth/auth.test.js b/src/plugins/auth/auth.test.js
index 6dbf822..31a7c42 100644
--- a/src/plugins/auth/auth.test.js
+++ b/src/plugins/auth/auth.test.js
@@ -3,11 +3,11 @@ const mockActualTestWarnFn = jest.fn()
 const mockActualTestInfoFn = jest.fn()
 
 jest.mock('~/src/helpers/logging/logger.js', () => ({
-  createLogger: jest.fn().mockReturnValue({
+  logger: {
     error: mockActualTestErrorFn,
     warn: mockActualTestWarnFn,
     info: mockActualTestInfoFn
-  })
+  }
 }))
 
 jest.mock('~/src/config/index.js', () => ({
diff --git a/src/plugins/auth/index.js b/src/plugins/auth/index.js
index aa4ff81..40dbbee 100644
--- a/src/plugins/auth/index.js
+++ b/src/plugins/auth/index.js
@@ -1,15 +1,13 @@
 import Jwt from '@hapi/jwt'
 
 import { config } from '~/src/config/index.js'
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import { getUserScopes } from '~/src/service/entitlements/service.js'
 
 const oidcJwksUri = config.get('oidcJwksUri')
 const oidcVerifyAud = config.get('oidcVerifyAud')
 const oidcVerifyIss = config.get('oidcVerifyIss')
 
-const logger = createLogger()
-
 /**
  * Validates user credentials from JWT token
  * @param {Artifacts<UserCredentials>} artifacts - JWT artifacts
diff --git a/src/routes/admin.js b/src/routes/admin.js
index f465d9d..8ee84ca 100644
--- a/src/routes/admin.js
+++ b/src/routes/admin.js
@@ -1,15 +1,13 @@
 import { Scopes } from '@defra/forms-model'
 import Joi from 'joi'
 
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import {
   deleteDlqMessage,
   receiveDlqMessages,
   redriveDlqMessages
 } from '~/src/messaging/event.js'
 
-const logger = createLogger()
-
 const OK_RESPONSE = 200
 
 const messageIdSchema = Joi.object({
diff --git a/src/server.js b/src/server.js
index f7aba04..801ad86 100644
--- a/src/server.js
+++ b/src/server.js
@@ -2,9 +2,7 @@ import { getErrorMessage } from '@defra/forms-model'
 
 import { createServer } from '~/src/api/server.js'
 import { config } from '~/src/config/index.js'
-import { createLogger } from '~/src/helpers/logging/logger.js'
-
-const logger = createLogger()
+import { logger } from '~/src/helpers/logging/logger.js'
 
 process.on('unhandledRejection', (err) => {
   logger.error(
diff --git a/src/service/entitlements/service.js b/src/service/entitlements/service.js
index f686316..d689ab5 100644
--- a/src/service/entitlements/service.js
+++ b/src/service/entitlements/service.js
@@ -1,12 +1,11 @@
 import Boom from '@hapi/boom'
 
 import { config } from '~/src/config/index.js'
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import { getJson } from '~/src/lib/fetch.js'
 
 const entitlementUrl = config.get('entitlementUrl')
 const entitlementsEndpoint = new URL('/', entitlementUrl)
-const logger = createLogger()
 
 /**
  * Fetches user scopes from the entitlements API
diff --git a/src/service/entitlements/service.test.js b/src/service/entitlements/service.test.js
index 3708142..9be47ce 100644
--- a/src/service/entitlements/service.test.js
+++ b/src/service/entitlements/service.test.js
@@ -37,7 +37,7 @@ describe('entitlements service', () => {
       }
     }))
     jest.doMock('~/src/helpers/logging/logger.js', () => ({
-      createLogger: jest.fn().mockReturnValue(mockLogger)
+      logger: mockLogger
     }))
 
     const fetchModule = await import('~/src/lib/fetch.js')
diff --git a/src/service/events.js b/src/service/events.js
index 171f14b..ca57164 100644
--- a/src/service/events.js
+++ b/src/service/events.js
@@ -2,11 +2,9 @@ import { formAdapterSubmissionMessagePayloadSchema } from '@defra/forms-engine-p
 import { getErrorMessage } from '@defra/forms-model'
 import Joi from 'joi'
 
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import { deleteEventMessage } from '~/src/messaging/event.js'
 
-const logger = createLogger()
-
 /**
  * @param {Message} message
  * @returns {FormAdapterSubmissionMessage}
diff --git a/src/service/events.test.js b/src/service/events.test.js
index fcaa60b..1701e55 100644
--- a/src/service/events.test.js
+++ b/src/service/events.test.js
@@ -18,7 +18,13 @@ import {
 } from '~/src/service/events.js'
 
 jest.mock('~/src/messaging/event.js')
-jest.mock('~/src/helpers/logging/logger.js')
+jest.mock('~/src/helpers/logging/logger.js', () => ({
+  logger: {
+    info: jest.fn(),
+    error: jest.fn(),
+    debug: jest.fn()
+  }
+}))
 jest.mock('~/src/config/index.js', () => ({
   config: {
     get: jest.fn((key) => {
diff --git a/src/service/sharepoint.js b/src/service/sharepoint.js
index ffd240e..fc277ed 100644
--- a/src/service/sharepoint.js
+++ b/src/service/sharepoint.js
@@ -8,7 +8,7 @@ import {
 
 import { formMappingsSchema } from '~/src/config/form-mappings-schema.js'
 import { config } from '~/src/config/index.js'
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import { getFormDefinition } from '~/src/lib/manager.js'
 import {
   addItemsByFieldName,
@@ -16,7 +16,6 @@ import {
 } from '~/src/service/ms-graph.js'
 import { getGraphClient } from '~/src/service/sharepoint-client.js'
 
-const logger = createLogger()
 const graphClient = getGraphClient()
 
 /**
diff --git a/src/service/sharepoint.test.js b/src/service/sharepoint.test.js
index 95a589f..00cb3fb 100644
--- a/src/service/sharepoint.test.js
+++ b/src/service/sharepoint.test.js
@@ -26,11 +26,11 @@ import {
 } from '~/src/service/sharepoint.js'
 
 jest.mock('~/src/helpers/logging/logger.js', () => ({
-  createLogger: () => ({
+  logger: {
     info: jest.fn(),
     error: jest.fn(),
     debug: jest.fn()
-  })
+  }
 }))
 jest.mock('~/src/lib/manager.js')
 jest.mock('~/src/service/ms-graph.js')
diff --git a/src/tasks/receive-messages.js b/src/tasks/receive-messages.js
index 2cd2461..ff61874 100644
--- a/src/tasks/receive-messages.js
+++ b/src/tasks/receive-messages.js
@@ -1,14 +1,12 @@
 import { getErrorMessage } from '@defra/forms-model'
 
-import { createLogger } from '~/src/helpers/logging/logger.js'
+import { logger } from '~/src/helpers/logging/logger.js'
 import {
   receiveEventMessages,
   receiveMessageTimeout
 } from '~/src/messaging/event.js'
 import { handleEvent } from '~/src/service/index.js'
 
-const logger = createLogger()
-
 /**
  * @returns {Promise<void>}
  */
diff --git a/src/tasks/receive-messages.test.js b/src/tasks/receive-messages.test.js
index c327ce6..2e5440d 100644
--- a/src/tasks/receive-messages.test.js
+++ b/src/tasks/receive-messages.test.js
@@ -7,7 +7,13 @@ import { handleEvent } from '~/src/service/index.js'
 import { runTask, runTaskOnce } from '~/src/tasks/receive-messages.js'
 jest.mock('~/src/messaging/event.js')
 jest.mock('~/src/service/index.js')
-jest.mock('~/src/helpers/logging/logger.js')
+jest.mock('~/src/helpers/logging/logger.js', () => ({
+  logger: {
+    info: jest.fn(),
+    error: jest.fn(),
+    debug: jest.fn()
+  }
+}))
 
 /**
  * @returns {void}