diff --git a/api/src/constants/dates.ts b/api/src/constants/dates.ts
index 4093dde22c..00722e6895 100644
--- a/api/src/constants/dates.ts
+++ b/api/src/constants/dates.ts
@@ -1,4 +1,4 @@
-/**
+/*
  * Date formats.
  *
  * See BC Gov standards: https://www2.gov.bc.ca/gov/content/governments/services-for-government/policies-procedures/web-content-development-guides/writing-for-the-web/web-style-guide/numbers
@@ -11,7 +11,12 @@ export const AltDateFormat = 'YYYY/MM/DD'; // 2020/01/05
 
 export const AltDateFormatReverse = 'DD/MM/YYYY'; // 05/01/2020
 
-/**
+/*
  * Time formats.
  */
 export const DefaultTimeFormat = 'HH:mm:ss'; // 23:00:00
+
+/*
+ * Datetime formats.
+ */
+export const DefaultDateTimeFormat = `${DefaultDateFormat}T${DefaultTimeFormat}`; // 2020-01-05T23:00:00
diff --git a/api/src/services/import-services/capture/import-captures-strategy.test.ts b/api/src/services/import-services/capture/import-captures-strategy.test.ts
index b7df1d6eff..c5687cac27 100644
--- a/api/src/services/import-services/capture/import-captures-strategy.test.ts
+++ b/api/src/services/import-services/capture/import-captures-strategy.test.ts
@@ -22,18 +22,18 @@ describe('import-captures-service', () => {
         I1: { t: 's', v: 'RELEASE_LONGITUDE' },
         J1: { t: 's', v: 'RELEASE_COMMENT' },
         K1: { t: 's', v: 'CAPTURE_COMMENT' },
-        A2: { z: 'm/d/yy', t: 'd', v: '2024-10-10T07:00:00.000Z', w: '10/10/24' },
+        A2: { z: 'dd/mm/yyyy', t: 'd', v: new Date('2024-10-11T00:00:00'), w: '11/10/2024' },
         B2: { t: 's', v: 'Carl' },
         C2: { t: 's', v: '10:10:10' },
         D2: { t: 'n', w: '90', v: 90 },
         E2: { t: 'n', w: '100', v: 100 },
-        F2: { z: 'm/d/yy', t: 'd', v: '2024-10-10T07:00:00.000Z', w: '10/10/24' },
+        F2: { t: 's', v: '2024-10-11' },
         G2: { t: 's', v: '9:09' },
         H2: { t: 'n', w: '90', v: 90 },
         I2: { t: 'n', w: '90', v: 90 },
         J2: { t: 's', v: 'release' },
         K2: { t: 's', v: 'capture' },
-        A3: { z: 'm/d/yy', t: 'd', v: '2024-10-10T07:00:00.000Z', w: '10/10/24' },
+        A3: { z: 'yyyy-mm-dd', t: 'd', v: new Date('2024-10-11T07:00:00.000Z'), w: '2024-10-11' },
         B3: { t: 's', v: 'Carlita' },
         D3: { t: 'n', w: '90', v: 90 },
         E3: { t: 'n', w: '100', v: 100 },
diff --git a/api/src/utils/xlsx-utils/cell-utils.ts b/api/src/utils/xlsx-utils/cell-utils.ts
index 51e0f0a371..bfc8c91daa 100644
--- a/api/src/utils/xlsx-utils/cell-utils.ts
+++ b/api/src/utils/xlsx-utils/cell-utils.ts
@@ -111,7 +111,7 @@ export function isStringCellWithDateValue(cell: CellObject): false | string {
   }
 
   const matchedFormats = [DefaultDateFormat, DefaultDateFormatReverse, AltDateFormat, AltDateFormatReverse].filter(
-    (format) => dayjs(String(cell.v), format, true).isValid()
+    (format) => dayjs(String(cell.v), format).isValid()
   );
 
   // Ensure only one format matched
diff --git a/api/src/utils/xlsx-utils/worksheet-utils.ts b/api/src/utils/xlsx-utils/worksheet-utils.ts
index f989c76e5d..38812641ae 100644
--- a/api/src/utils/xlsx-utils/worksheet-utils.ts
+++ b/api/src/utils/xlsx-utils/worksheet-utils.ts
@@ -53,7 +53,7 @@ export const constructXLSXWorkbook = (file: MediaFile): xlsx.WorkBook => {
     cellDates: true,
     cellNF: true,
     cellHTML: false,
-    dateNF: 'yyyy-mm-dd HH:mm:ss',
+    dateNF: '_',
     raw: false
   });
 };