diff --git a/api/orders.js b/api/orders.js
index 147050e..4fb7152 100644
--- a/api/orders.js
+++ b/api/orders.js
@@ -63,6 +63,9 @@ router.post('/current/coupon', ensureCart, parseJSON, validate.coupon, validate.
 
   const coupon = await db.coupon.find(req.body.code)
 
+  if(!coupon)
+    throw new Error(`No such coupon: "${req.body.code}"`)
+
   const currentTransaction = origOrder
     .transactions.find(transaction => (
       transaction.payment_state === 'started'
diff --git a/db/models/order.js b/db/models/order.js
index c94645a..9193bff 100644
--- a/db/models/order.js
+++ b/db/models/order.js
@@ -151,12 +151,14 @@ order.addAddress = async function (transaction, address){
 order.updateTax = async function(transaction_uuid){
   const _order = await order.findForTransaction(transaction_uuid)
 
-  if(!_order.address)
-    throw new Error("Order has no address");
+  if(!_order.address){
+    debug("Skipping tax because order has no address yet")
+    return _order
+  }
 
   if(_order.address.state !== 'UT'){
     debug("Skipping tax for state: " + _order.address.state);
-    return
+    return _order
   }
 
   const {item_total_price, coupon_effective_discount} = _order.transactions.find(t => t.uuid === transaction_uuid)
diff --git a/pages/store/checkout/index.js b/pages/store/checkout/index.js
index fc02177..f31700f 100644
--- a/pages/store/checkout/index.js
+++ b/pages/store/checkout/index.js
@@ -21,6 +21,7 @@ CheckoutSummary.getInitialProps = async function({ctx: {axios}}){
 export default function CheckoutSummary({order: _order}){
   const user = useUser();
   const [order, updateOrder] = useState(_order)
+  const [couponError, setCouponError] = useState(null)
 
   const currentTransaction = order
     .transactions.find(transaction => (
@@ -45,9 +46,22 @@ export default function CheckoutSummary({order: _order}){
   const onCouponSubmit = async ev => {
     if(ev) ev.preventDefault()
 
+    setCouponError(null)
+
     const code = couponRef.current?.value
-    const {data: updatedOrder} = await axios.post(`/api/orders/current/coupon`, {code})
-    updateOrder(updatedOrder)
+
+    try {
+      const {data: updatedOrder} = await axios.post(`/api/orders/current/coupon`, {code})
+      console.log(order, updatedOrder)
+      updateOrder(updatedOrder)
+    } catch (err) {
+      console.log(err.response.data.errors)
+      const message = err?.response?.data?.error?.message
+         || err.response?.data?.errors?.find(e => e.param === 'code')?.msg
+         || 'Unknown error applying coupon'
+
+      setCouponError(message)
+    }
   }
 
   // For Stripe checkout
@@ -127,9 +141,9 @@ export default function CheckoutSummary({order: _order}){
             )
             : (
               <div className={styles.horizContainer} style={{maxWidth:'400px', margin: '0 auto'}}>
-                <Input inputRef={couponRef} label="" name="coupon" />
-                <div style={{maxWidth: '120px', marginLeft: '8px'}}>
-                  <Button onClick={onCouponSubmit} outline>Save Coupon</Button>
+                <Input inputRef={couponRef} label="" name="coupon" onChange={() => setCouponError(null)} error={couponError} />
+                <div style={{alignSelf:'flex-start', maxWidth: '120px', marginLeft: '8px'}}>
+                  <Button onClick={onCouponSubmit} outline>Apply Coupon</Button>
                 </div>
               </div>
             )