diff --git a/package.json b/package.json
index ba097038..04d7b820 100644
--- a/package.json
+++ b/package.json
@@ -61,6 +61,7 @@
   },
   "dependencies": {
     "@tommoor/slate-drop-or-paste-images": "0.5.1",
+    "aws-sdk": "^2.135.0",
     "babel-core": "^6.24.1",
     "babel-eslint": "^7.2.3",
     "babel-loader": "6.2.5",
diff --git a/server/api/auth.js b/server/api/auth.js
index 42752b47..51304e5d 100644
--- a/server/api/auth.js
+++ b/server/api/auth.js
@@ -47,6 +47,10 @@ router.post('auth.slack', async ctx => {
     await team.createFirstCollection(user.id);
   }
 
+  // Update user's avatar
+  await user.updateAvatar();
+  await user.save();
+
   ctx.body = {
     data: {
       user: await presentUser(ctx, user),
diff --git a/server/migrations/20171019071915-user-avatar-url.js b/server/migrations/20171019071915-user-avatar-url.js
new file mode 100644
index 00000000..5be75d52
--- /dev/null
+++ b/server/migrations/20171019071915-user-avatar-url.js
@@ -0,0 +1,12 @@
+module.exports = {
+  up: function(queryInterface, Sequelize) {
+    queryInterface.addColumn('users', 'avatarUrl', {
+      type: Sequelize.TEXT,
+      allowNull: true,
+    });
+  },
+
+  down: function(queryInterface, Sequelize) {
+    queryInterface.removeColumn('users', 'avatarUrl');
+  },
+};
diff --git a/server/models/User.js b/server/models/User.js
index 69158780..a2f29488 100644
--- a/server/models/User.js
+++ b/server/models/User.js
@@ -2,6 +2,7 @@
 import crypto from 'crypto';
 import bcrypt from 'bcrypt';
 import { DataTypes, sequelize, encryptedFields } from '../sequelize';
+import { uploadToS3FromUrl } from '../utils/s3';
 
 import JWT from 'jsonwebtoken';
 
@@ -18,6 +19,7 @@ const User = sequelize.define(
     email: { type: DataTypes.STRING },
     username: { type: DataTypes.STRING },
     name: DataTypes.STRING,
+    avatarUrl: { type: DataTypes.STRING, allowNull: true },
     password: DataTypes.VIRTUAL,
     passwordDigest: DataTypes.STRING,
     isAdmin: DataTypes.BOOLEAN,
@@ -66,6 +68,12 @@ User.prototype.verifyPassword = function(password) {
     });
   });
 };
+User.prototype.updateAvatar = async function() {
+  this.avatarUrl = await uploadToS3FromUrl(
+    this.slackData.image_192,
+    `avatars/${this.id}`
+  );
+};
 
 const setRandomJwtSecret = model => {
   model.jwtSecret = crypto.randomBytes(64).toString('hex');
diff --git a/server/presenters/user.js b/server/presenters/user.js
index f545cd66..1d064ace 100644
--- a/server/presenters/user.js
+++ b/server/presenters/user.js
@@ -8,7 +8,8 @@ function present(ctx: Object, user: User) {
     id: user.id,
     username: user.username,
     name: user.name,
-    avatarUrl: user.slackData ? user.slackData.image_192 : null,
+    avatarUrl: user.avatarUrl ||
+      (user.slackData ? user.slackData.image_192 : null),
   };
 }
 
diff --git a/server/slack.js b/server/slack.js
index 62bb75eb..ab45d669 100644
--- a/server/slack.js
+++ b/server/slack.js
@@ -15,7 +15,6 @@ export async function request(endpoint: string, body: Object) {
   } catch (e) {
     throw httpErrors.BadRequest();
   }
-  console.log('DATA', data);
   if (!data.ok) throw httpErrors.BadRequest(data.error);
 
   return data;
diff --git a/server/utils/s3.js b/server/utils/s3.js
index 65351a98..1837f7d2 100644
--- a/server/utils/s3.js
+++ b/server/utils/s3.js
@@ -1,5 +1,13 @@
+// @flow
 import crypto from 'crypto';
 import moment from 'moment';
+import AWS from 'aws-sdk';
+import fetch from 'isomorphic-fetch';
+
+AWS.config.update({
+  accessKeyId: process.env.AWS_ACCESS_KEY_ID,
+  secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY,
+});
 
 const makePolicy = () => {
   const policy = {
@@ -19,7 +27,7 @@ const makePolicy = () => {
   return new Buffer(JSON.stringify(policy)).toString('base64');
 };
 
-const signPolicy = policy => {
+const signPolicy = (policy: any) => {
   const signature = crypto
     .createHmac('sha1', process.env.AWS_SECRET_ACCESS_KEY)
     .update(policy)
@@ -28,4 +36,25 @@ const signPolicy = policy => {
   return signature;
 };
 
-export { makePolicy, signPolicy };
+const uploadToS3FromUrl = async (url: string, key: string) => {
+  const s3 = new AWS.S3();
+
+  try {
+    const res = await fetch(url);
+    const buffer = await res.buffer();
+    await s3
+      .putObject({
+        Bucket: process.env.AWS_S3_UPLOAD_BUCKET_NAME,
+        Key: key,
+        ContentType: res.headers['content-type'],
+        ContentLength: res.headers['content-length'],
+        Body: buffer,
+      })
+      .promise();
+    return `https://s3.amazonaws.com/${process.env.AWS_S3_UPLOAD_BUCKET_NAME}/${key}`;
+  } catch (_e) {
+    return undefined;
+  }
+};
+
+export { makePolicy, signPolicy, uploadToS3FromUrl };
diff --git a/yarn.lock b/yarn.lock
index 10b24544..d70cdf87 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -339,6 +339,21 @@ autoprefixer@^6.3.1:
     postcss "^5.2.16"
     postcss-value-parser "^3.2.3"
 
+aws-sdk@^2.135.0:
+  version "2.135.0"
+  resolved "https://registry.yarnpkg.com/aws-sdk/-/aws-sdk-2.135.0.tgz#81f4a47b99212f2f236bf5b11b0b3a3a02086db4"
+  dependencies:
+    buffer "4.9.1"
+    crypto-browserify "1.0.9"
+    events "^1.1.1"
+    jmespath "0.15.0"
+    querystring "0.2.0"
+    sax "1.2.1"
+    url "0.10.3"
+    uuid "3.1.0"
+    xml2js "0.4.17"
+    xmlbuilder "4.2.1"
+
 aws-sign2@~0.6.0:
   version "0.6.0"
   resolved "https://registry.yarnpkg.com/aws-sign2/-/aws-sign2-0.6.0.tgz#14342dd38dbcc94d0e5b87d763cd63612c0e794f"
@@ -1268,7 +1283,7 @@ buffer-xor@^1.0.2:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/buffer-xor/-/buffer-xor-1.0.3.tgz#26e61ed1422fb70dd42e6e36729ed51d855fe8d9"
 
-buffer@^4.3.0, buffer@^4.9.0:
+buffer@4.9.1, buffer@^4.3.0, buffer@^4.9.0:
   version "4.9.1"
   resolved "https://registry.yarnpkg.com/buffer/-/buffer-4.9.1.tgz#6d1bb601b07a4efced97094132093027c95bc298"
   dependencies:
@@ -1959,6 +1974,10 @@ cryptiles@2.x.x:
   dependencies:
     boom "2.x.x"
 
+crypto-browserify@1.0.9:
+  version "1.0.9"
+  resolved "https://registry.yarnpkg.com/crypto-browserify/-/crypto-browserify-1.0.9.tgz#cc5449685dfb85eb11c9828acc7cb87ab5bbfcc0"
+
 crypto-browserify@^3.11.0:
   version "3.11.1"
   resolved "https://registry.yarnpkg.com/crypto-browserify/-/crypto-browserify-3.11.1.tgz#948945efc6757a400d6e5e5af47194d10064279f"
@@ -2923,7 +2942,7 @@ event-stream@~3.3.0:
     stream-combiner "~0.0.4"
     through "~2.3.1"
 
-events@^1.0.0:
+events@^1.0.0, events@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/events/-/events-1.1.1.tgz#9ebdb7635ad099c70dcc4c2a1f5004288e8bd924"
 
@@ -4816,6 +4835,10 @@ jest-validate@^20.0.3:
     leven "^2.1.0"
     pretty-format "^20.0.3"
 
+jmespath@0.15.0:
+  version "0.15.0"
+  resolved "https://registry.yarnpkg.com/jmespath/-/jmespath-0.15.0.tgz#a3f222a9aae9f966f5d27c796510e28091764217"
+
 joi@^6.10.1, joi@~6.10.1:
   version "6.10.1"
   resolved "https://registry.yarnpkg.com/joi/-/joi-6.10.1.tgz#4d50c318079122000fe5f16af1ff8e1917b77e06"
@@ -7806,7 +7829,11 @@ sane@~1.6.0:
     walker "~1.0.5"
     watch "~0.10.0"
 
-sax@^1.2.1, sax@~1.2.1:
+sax@1.2.1:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.1.tgz#7b8e656190b228e81a66aea748480d828cd2d37a"
+
+sax@>=0.6.0, sax@^1.2.1, sax@~1.2.1:
   version "1.2.4"
   resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.4.tgz#2816234e2378bddc4e5354fab5caa895df7100d9"
 
@@ -8849,16 +8876,16 @@ url-to-options@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/url-to-options/-/url-to-options-1.0.1.tgz#1505a03a289a48cbd7a434efbaeec5055f5633a9"
 
-url@^0.11.0:
-  version "0.11.0"
-  resolved "https://registry.yarnpkg.com/url/-/url-0.11.0.tgz#3838e97cfc60521eb73c525a8e55bfdd9e2e28f1"
+url@0.10.3, url@~0.10.1:
+  version "0.10.3"
+  resolved "https://registry.yarnpkg.com/url/-/url-0.10.3.tgz#021e4d9c7705f21bbf37d03ceb58767402774c64"
   dependencies:
     punycode "1.3.2"
     querystring "0.2.0"
 
-url@~0.10.1:
-  version "0.10.3"
-  resolved "https://registry.yarnpkg.com/url/-/url-0.10.3.tgz#021e4d9c7705f21bbf37d03ceb58767402774c64"
+url@^0.11.0:
+  version "0.11.0"
+  resolved "https://registry.yarnpkg.com/url/-/url-0.11.0.tgz#3838e97cfc60521eb73c525a8e55bfdd9e2e28f1"
   dependencies:
     punycode "1.3.2"
     querystring "0.2.0"
@@ -8899,14 +8926,14 @@ uuid@2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-2.0.2.tgz#48bd5698f0677e3c7901a1c46ef15b1643794726"
 
+uuid@3.1.0, uuid@^3.0.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.1.0.tgz#3dd3d3e790abc24d7b0d3a034ffababe28ebbc04"
+
 uuid@^2.0.1, uuid@^2.0.3:
   version "2.0.3"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-2.0.3.tgz#67e2e863797215530dff318e5bf9dcebfd47b21a"
 
-uuid@^3.0.0:
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.1.0.tgz#3dd3d3e790abc24d7b0d3a034ffababe28ebbc04"
-
 v8flags@^2.0.2:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/v8flags/-/v8flags-2.1.1.tgz#aab1a1fa30d45f88dd321148875ac02c0b55e5b4"
@@ -9202,6 +9229,19 @@ xml-name-validator@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/xml-name-validator/-/xml-name-validator-2.0.1.tgz#4d8b8f1eccd3419aa362061becef515e1e559635"
 
+xml2js@0.4.17:
+  version "0.4.17"
+  resolved "https://registry.yarnpkg.com/xml2js/-/xml2js-0.4.17.tgz#17be93eaae3f3b779359c795b419705a8817e868"
+  dependencies:
+    sax ">=0.6.0"
+    xmlbuilder "^4.1.0"
+
+xmlbuilder@4.2.1, xmlbuilder@^4.1.0:
+  version "4.2.1"
+  resolved "https://registry.yarnpkg.com/xmlbuilder/-/xmlbuilder-4.2.1.tgz#aa58a3041a066f90eaa16c2f5389ff19f3f461a5"
+  dependencies:
+    lodash "^4.0.0"
+
 "xtend@>=4.0.0 <4.1.0-0", xtend@^4.0.0, xtend@^4.0.1, xtend@~4.0.1:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/xtend/-/xtend-4.0.1.tgz#a5c6d532be656e23db820efb943a1f04998d63af"