diff --git a/src/App.js b/src/App.js
index 02dac02..9e2e7df 100644
--- a/src/App.js
+++ b/src/App.js
@@ -134,7 +134,7 @@ function App() {
                 <p>You are accessing the following service: <strong>{displayName}</strong></p>
                 <div className="d-flex column align-items-center">
                   <p className="bottom-0">Select your home organization:</p>
-                  <a href={`https://service.seamlessaccess.org/ds/?entityID=${entityID}&return=${returnUrl}`} className="d-flex sa-button">
+                  <a href={`https://service.seamlessaccess.org/ds/?entityID=${encodeURIComponent(entityID)}&return=${encodeURIComponent(returnUrl)}`} className="d-flex sa-button">
                     <div className="sa-button-logo-wrap">
                       <img src="https://service.seamlessaccess.org/sa-white.svg" alt="Seamless Access Logo" className="sa-button-logo"/>
                     </div>