diff --git a/backend/api/services/sales_spreadsheet.py b/backend/api/services/sales_spreadsheet.py
index fa95175c6..6342496e2 100644
--- a/backend/api/services/sales_spreadsheet.py
+++ b/backend/api/services/sales_spreadsheet.py
@@ -347,18 +347,25 @@ def validate_spreadsheet(data, user_organization=None, skip_authorization=False)
         )
 
     row = start_row
+    vin_dict = {}
+    duplicates = {}
 
     while row < min((MAX_READ_ROWS + start_row), sheet.nrows):
         row_contents = sheet.row(row)
         model_year = str(row_contents[0].value).strip()
         make = str(row_contents[1].value).strip()
         model_name = str(row_contents[2].value).strip()
-        vin = str(row_contents[3].value)
+        vin = str(row_contents[3].value).strip()
         date = str(row_contents[4].value).strip()
         row_contains_content = False
         if len(model_year) > 0 or len(make) > 0 or len(model_name) > 0 or \
                 len(date) > 0:
             row_contains_content = True
+        if row_contains_content:
+            if vin in vin_dict:
+                vin_dict[vin].append(row + 1)
+            else:
+                vin_dict[vin] = [row + 1]
 
         if row_contains_content and row_contents[4].ctype != xlrd.XL_CELL_DATE:
             raise ValidationError(
@@ -371,7 +378,14 @@ def validate_spreadsheet(data, user_organization=None, skip_authorization=False)
                 'the row and try again.'
             )
         row += 1
-
+    duplicates = {vin: rows for vin, rows in vin_dict.items() if len(rows) > 1}
+    if duplicates:
+            error_message = 'Spreadsheet contains duplicate VINs.|'
+            for vin, rows in duplicates.items():
+                row_list = ', '.join(map(str, rows))
+                error_message += f'VIN {vin}: rows {row_list}|'
+            error_message += 'Please make changes to the spreadsheet and try again.'
+            raise ValidationError(error_message)
     return True
 
 
diff --git a/frontend/src/app/components/FileDropArea.js b/frontend/src/app/components/FileDropArea.js
index d843defbe..880bfb7ae 100644
--- a/frontend/src/app/components/FileDropArea.js
+++ b/frontend/src/app/components/FileDropArea.js
@@ -31,7 +31,9 @@ const FileDropArea = (props) => {
       }
     }
   }
-
+  const formattedErrorMessage = errorMessage ? errorMessage.split('|').map((msg, index) => (
+    <div key={index}>{msg}</div>
+  )) : null;
   return (
     <div className="row">
       <div
@@ -40,7 +42,7 @@ const FileDropArea = (props) => {
         <div className="bordered">
           {errorMessage && (
             <div className="alert alert-danger mb-2" role="alert">
-              {errorMessage}
+              {formattedErrorMessage}
             </div>
           )}
           <div className="panel panel-default">