diff --git a/src/actions/filesDropped/constants.js b/src/actions/filesDropped/constants.js
new file mode 100644
index 000000000..f3f10fd15
--- /dev/null
+++ b/src/actions/filesDropped/constants.js
@@ -0,0 +1,18 @@
+/*
+    Defines acceptable file types for the auspice drag & drop functionality.
+*/
+
+const csv_file_types = ["text/csv", "application/vnd.ms-excel"];
+
+// Add MacOS & Linux .tsv to accepted file types
+const accepted_file_types = csv_file_types.concat("text/tab-separated-values");
+
+// Handle Windows .tsv edge case with empty file type
+const is_windows_tsv = (file) => file.type === "" && file.name.endsWith('.tsv');
+
+const is_csv_or_tsv = (file) => accepted_file_types.includes(file.type) || is_windows_tsv(file);
+
+export {
+  csv_file_types,
+  is_csv_or_tsv
+};
diff --git a/src/actions/filesDropped/index.js b/src/actions/filesDropped/index.js
index d34a7f351..489eb8619 100644
--- a/src/actions/filesDropped/index.js
+++ b/src/actions/filesDropped/index.js
@@ -1,5 +1,6 @@
 import { warningNotification } from "../notifications";
 import handleMetadata from "./metadata";
+import { is_csv_or_tsv } from "./constants";
 
 
 /**
@@ -16,7 +17,8 @@ const handleFilesDropped = (files) => (dispatch, getState) => {
   }
 
   const file = files[0];
-  if (file.type === "text/csv" || file.type === "text/tab-separated-values") {
+
+  if (is_csv_or_tsv(file)) {
     return handleMetadata(dispatch, getState, file);
   }
 
diff --git a/src/actions/filesDropped/metadata.js b/src/actions/filesDropped/metadata.js
index 13332e4ff..3636a168c 100644
--- a/src/actions/filesDropped/metadata.js
+++ b/src/actions/filesDropped/metadata.js
@@ -1,6 +1,7 @@
 import Papa from "papaparse";
 import { errorNotification, successNotification, warningNotification } from "../notifications";
 import { ADD_COLOR_BYS } from "../types";
+import { csv_file_types, is_csv_or_tsv } from "./constants";
 
 
 /**
@@ -12,7 +13,7 @@ import { ADD_COLOR_BYS } from "../types";
  * @param {DataTransfer} file a DataTransfer object
  */
 const parseCsv = (file) => new Promise((resolve, reject) => {
-  if (!["text/csv", "text/tab-separated-values"].includes(file.type)) {
+  if (!(is_csv_or_tsv(file))) {
     reject(new Error("Cannot parse this filetype"));
   }
   Papa.parse(file, {
@@ -25,7 +26,7 @@ const parseCsv = (file) => new Promise((resolve, reject) => {
     },
     encoding: "UTF-8",
     comments: "#",
-    delimiter: file.type === "text/csv" ? "," : "\t",
+    delimiter: (csv_file_types.includes(file.type)) ? "," : "\t",
     skipEmptyLines: true,
     dynamicTyping: false
   });