diff --git a/README.md b/README.md
index 2ece100..98dda73 100644
--- a/README.md
+++ b/README.md
@@ -37,7 +37,7 @@ Note the format of the date (`YYYY-MM-DD`) and the fact that multiple chores can
 
 ##### Service account
 
-Create a service account using [these instructions](https://developers.google.com/android/management/service-account). Once it's created, share the previously created spreadsheet with the service account's address. View-only permissions should be fine; we're only reading data from the sheet.
+Create a service account using [these instructions](https://developers.google.com/android/management/service-account). Once it's created, share the previously created spreadsheet with the service account's address. You will need both Read and Write permissions (`https://www.googleapis.com/auth/spreadsheets`) for this to work.
 
 #### Your server
 
diff --git a/server.js b/server.js
index e2d9af3..2a8dad3 100644
--- a/server.js
+++ b/server.js
@@ -46,7 +46,7 @@ app.action(
   },
   async ({ action, body }) => {
     if (!action || !body || !body.user || !body.channel || !body.message) return;
-    markChoreDone(action.action_id, body.user.id, body.channel.id, body.message.ts,
+      await markChoreDone(action.action_id, body.user, body.channel.id, body.message.ts,
       body.message.blocks);
   }
 );
diff --git a/utilities/getChores.js b/utilities/getChores.js
index 04890c2..b43ac1b 100644
--- a/utilities/getChores.js
+++ b/utilities/getChores.js
@@ -1,4 +1,4 @@
-//node pacakges
+//node packages
 const { google } = require("googleapis");
 const moment = require("moment-timezone");
 require("dotenv").config();
diff --git a/utilities/markChoreDone.js b/utilities/markChoreDone.js
index d2bf5f9..6ed4dd1 100644
--- a/utilities/markChoreDone.js
+++ b/utilities/markChoreDone.js
@@ -1,26 +1,86 @@
+//node packages
+const {google} = require("googleapis");
+require("dotenv").config();
+
 //local packages
 const {
-  app: {
-    client: {
-      chat: { update }
+    app: {
+        client: {
+            chat: { update }
+        }
     }
-  }
 } = require("./bolt.js");
+const privatekey = require("../keys/sheets-api.json");
 
 //globals
 const TOKEN = process.env.SLACK_BOT_TOKEN;
+const SPREADSHEET_ID = process.env.SPREADSHEET_ID;
+const GDRIVE_EMAIL = process.env.GDRIVE_EMAIL;
+
+const jwtClient = new google.auth.JWT(
+    privatekey.client_email,
+    null,
+    privatekey.private_key,
+    ["https://www.googleapis.com/auth/spreadsheets"],
+    GDRIVE_EMAIL
+);
+
+const setCompletedBy = async (user, date, choretext) => {
+    const sheets = google.sheets({
+        version: "v4",
+        auth: jwtClient
+    });
+
+    jwtClient.authorize(err => console.log(err ? err : "Successfully connected!"));
+
+    try {
+        const {data} = await sheets.spreadsheets.values.get({
+            spreadsheetId: SPREADSHEET_ID,
+            range: "A2:B"
+        });
+        for (let n = 0; n < data.values.length; n++) {
+            if (data.values[n][1] === choretext && data.values[n][0] === date) {
+                await sheets.spreadsheets.values.update({
+                    spreadsheetId: SPREADSHEET_ID,
+                    range: `Sheet1!C${n + 2}:D${n + 2}`,
+                    valueInputOption: 'USER_ENTERED',
+                    resource: {values: [[user.name, user.id]]}
+                });
+                break;
+            }
+        }
+    } catch (error) {
+        console.error(error);
+    }
+};
 
 //helper functions
 const crossOffAndTag = (user, index, blocks) => {
-  const choreText = blocks[index + 2].text.text.replace("&gt;", "");
-  blocks[index + 2].text.text = `>~${choreText}~ Completed by <@${user}>`;
-  delete blocks[index + 2].accessory;
-  return blocks;
+    const choreText = blocks[index + 2].text.text.replace("&gt;", "");
+    blocks[index + 2].text.text = `>~${choreText}~ Completed by <@${user}>`;
+    delete blocks[index + 2].accessory;
+    return blocks;
+};
+
+const markChoreDone = async (index, user, channel, ts, initialBlocks) => {
+    await setCompletedBy(user, formatDate(new Date(ts * 1000)), initialBlocks[parseInt(index) + 2]
+        .text.text.replace("&gt;", ""));
+    const blocks = crossOffAndTag(user.id, parseInt(index), initialBlocks);
+    update({ token: TOKEN, channel, ts, blocks });
 };
 
-const markChoreDone = (index, user, channel, ts, initialBlocks) => {
-  const blocks = crossOffAndTag(user, parseInt(index), initialBlocks);
-  update({ token: TOKEN, channel, ts, blocks });
+const formatDate = (date) => {
+    var d = new Date(date),
+        month = '' + (d.getMonth() + 1),
+        day = '' + d.getDate(),
+        year = d.getFullYear();
+
+    if (month.length < 2)
+        month = '0' + month;
+    if (day.length < 2)
+        day = '0' + day;
+
+    return [year, month, day].join('-');
 };
 
 module.exports = { markChoreDone };
diff --git a/utilities/notify.js b/utilities/notify.js
index 3458851..44ab42c 100644
--- a/utilities/notify.js
+++ b/utilities/notify.js
@@ -51,7 +51,7 @@ const postToSlack = chores => postSlackMessage("Today's chores have been posted!
   buildMarkdownSection(randomPhrase("greeting")),
   buildMarkdownSection("Tonight's chores:"),
   ...chores.map((c, i) => buildChoreElement(c, i)),
-  buildMarkdownSection(randomPhrase("request") + " If you have any questions " + 
+  buildMarkdownSection(randomPhrase("request") + " If you have any questions " +
     ":thinking_face: please reach out to the vice president!")
 ]);