diff --git a/CHANGELOG.md b/CHANGELOG.md
index d6812c4c..0c0c7f73 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -76,6 +76,7 @@
 * Create Jest/RTL test for RequestsFilters.js. Refs UIREQ-937.
 * Add "itemId" parameter to "allowed-service-points" endpoint. Refs UIREQ-1030.
 * Use current optional dependencies. Refs UIREQ-1031.
+* Update Requests error messages. Refs UIREQ-1036.
 
 ## [8.0.2](https://github.com/folio-org/ui-requests/tree/v8.0.2) (2023-03-29)
 [Full Changelog](https://github.com/folio-org/ui-requests/compare/v8.0.1...v8.0.2)
diff --git a/src/routes/RequestsRoute.js b/src/routes/RequestsRoute.js
index 80445306..3c7b7087 100644
--- a/src/routes/RequestsRoute.js
+++ b/src/routes/RequestsRoute.js
@@ -211,12 +211,30 @@ export const REQUEST_ERROR_MESSAGE_CODE = {
   REQUEST_NOT_ALLOWED_FOR_PATRON_TITLE_COMBINATION: 'REQUEST_NOT_ALLOWED_FOR_PATRON_TITLE_COMBINATION',
   SERVICE_POINT_IS_NOT_PICKUP_LOCATION: 'SERVICE_POINT_IS_NOT_PICKUP_LOCATION',
   REQUEST_PICKUP_SERVICE_POINT_IS_NOT_ALLOWED: 'REQUEST_PICKUP_SERVICE_POINT_IS_NOT_ALLOWED',
+  REQUEST_LEVEL_IS_NOT_ALLOWED: 'REQUEST_LEVEL_IS_NOT_ALLOWED',
+  FULFILLMENT_PREFERENCE_IS_NOT_ALLOWED: 'FULFILLMENT_PREFERENCE_IS_NOT_ALLOWED',
+  REQUESTER_ALREADY_HAS_LOAN_FOR_ONE_OF_INSTANCES_ITEMS: 'REQUESTER_ALREADY_HAS_LOAN_FOR_ONE_OF_INSTANCES_ITEMS',
+  REQUESTER_ALREADY_HAS_THIS_ITEM_ON_LOAN: 'REQUESTER_ALREADY_HAS_THIS_ITEM_ON_LOAN',
+  CANNOT_CREATE_PAGE_TLR_WITHOUT_ITEM_ID: 'CANNOT_CREATE_PAGE_TLR_WITHOUT_ITEM_ID',
+  HOLD_AND_RECALL_TLR_NOT_ALLOWED_PAGEABLE_AVAILABLE_ITEM_FOUND: 'HOLD_AND_RECALL_TLR_NOT_ALLOWED_PAGEABLE_AVAILABLE_ITEM_FOUND',
+  USER_CANNOT_BE_PROXY_FOR_THEMSELVES: 'USER_CANNOT_BE_PROXY_FOR_THEMSELVES',
+  ITEM_ALREADY_REQUESTED: 'ITEM_ALREADY_REQUESTED',
+  HOLD_SHELF_REQUESTS_REQUIRE_PICKUP_SERVICE_POINT: 'HOLD_SHELF_REQUESTS_REQUIRE_PICKUP_SERVICE_POINT',
 };
 
 export const REQUEST_ERROR_MESSAGE_TRANSLATION_KEYS = {
   [REQUEST_ERROR_MESSAGE_CODE.REQUEST_NOT_ALLOWED_FOR_PATRON_TITLE_COMBINATION]: 'ui-requests.errors.requestNotAllowedForPatronTitleCombination',
   [REQUEST_ERROR_MESSAGE_CODE.SERVICE_POINT_IS_NOT_PICKUP_LOCATION]: 'ui-requests.errors.servicePointIsNotPickupLocation',
   [REQUEST_ERROR_MESSAGE_CODE.REQUEST_PICKUP_SERVICE_POINT_IS_NOT_ALLOWED]: 'ui-requests.errors.requestPickupServicePointIsNotAllowed',
+  [REQUEST_ERROR_MESSAGE_CODE.REQUEST_LEVEL_IS_NOT_ALLOWED]: 'ui-requests.errors.requestLevelIsNotAllowed',
+  [REQUEST_ERROR_MESSAGE_CODE.FULFILLMENT_PREFERENCE_IS_NOT_ALLOWED]: 'ui-requests.errors.fulfillmentPreferenceIsNotAllowed',
+  [REQUEST_ERROR_MESSAGE_CODE.REQUESTER_ALREADY_HAS_LOAN_FOR_ONE_OF_INSTANCES_ITEMS]: 'ui-requests.errors.requesterAlreadyHasLoanForOneOfInstancesItems',
+  [REQUEST_ERROR_MESSAGE_CODE.REQUESTER_ALREADY_HAS_THIS_ITEM_ON_LOAN]: 'ui-requests.errors.requesterAlreadyHasThisItemOnLoan',
+  [REQUEST_ERROR_MESSAGE_CODE.CANNOT_CREATE_PAGE_TLR_WITHOUT_ITEM_ID]: 'ui-requests.errors.cannotCreatePageTlrWithoutItemId',
+  [REQUEST_ERROR_MESSAGE_CODE.HOLD_AND_RECALL_TLR_NOT_ALLOWED_PAGEABLE_AVAILABLE_ITEM_FOUND]: 'ui-requests.errors.holdAndRecallTlrNotAllowedPageableAvailableItemFound',
+  [REQUEST_ERROR_MESSAGE_CODE.USER_CANNOT_BE_PROXY_FOR_THEMSELVES]: 'ui-requests.errors.userCannotBeProxyForThemselves',
+  [REQUEST_ERROR_MESSAGE_CODE.ITEM_ALREADY_REQUESTED]: 'ui-requests.errors.itemAlreadyRequested',
+  [REQUEST_ERROR_MESSAGE_CODE.HOLD_SHELF_REQUESTS_REQUIRE_PICKUP_SERVICE_POINT]: 'ui-requests.errors.holdShelfRequestsRequirePickupServicePoint',
 };
 
 export const getRequestErrorMessage = (error, intl) => {
diff --git a/translations/ui-requests/en.json b/translations/ui-requests/en.json
index 799ec98e..af57a67c 100644
--- a/translations/ui-requests/en.json
+++ b/translations/ui-requests/en.json
@@ -88,6 +88,15 @@
   "errors.requestNotAllowedForPatronTitleCombination": "Hold requests are not allowed for this patron and title combination",
   "errors.servicePointIsNotPickupLocation": "Service point is not a Pickup location",
   "errors.requestPickupServicePointIsNotAllowed": "One or more Pickup locations are no longer available",
+  "errors.requestLevelIsNotAllowed": "Request level must be one of the following: \"Item\", \"Title\"",
+  "errors.fulfillmentPreferenceIsNotAllowed": "Fulfillment preference must be one of the following: Hold Shelf, Delivery",
+  "errors.requesterAlreadyHasLoanForOneOfInstancesItems": "This requester already has a loan for one of the instance's items",
+  "errors.requesterAlreadyHasThisItemOnLoan": "This requester already has this item on loan",
+  "errors.cannotCreatePageTlrWithoutItemId": "Cannot create a title level page request for this instance ID with no item ID",
+  "errors.holdAndRecallTlrNotAllowedPageableAvailableItemFound": "Hold/Recall title level request not allowed: pageable available item found for instance",
+  "errors.userCannotBeProxyForThemselves": "User cannot be proxy for themselves",
+  "errors.itemAlreadyRequested": "Not allowed to move title level page request to the same item",
+  "errors.holdShelfRequestsRequirePickupServicePoint": "Hold shelf fulfillment requests require a Pickup service point",
 
   "actions.label": "Actions",
   "actions.edit": "Edit",