diff --git a/chia/wallet/coin_selection.py b/chia/wallet/coin_selection.py
index d26e1f5cd7..d9b5696040 100644
--- a/chia/wallet/coin_selection.py
+++ b/chia/wallet/coin_selection.py
@@ -73,28 +73,28 @@ async def select_coins(
         if coin.amount < amount:
             smaller_coin_sum += coin.amount
             smaller_coins.append(coin)
-    if smaller_coin_sum == amount:
-        if len(smaller_coins) < 500:
-            log.debug(
-                f"Selected all smaller coins because they equate to an exact match of the target.: {smaller_coins}"
-            )
-            return set(smaller_coins)
-        else:
-            smallest_coin = select_smallest_coin_over_target(smaller_coins, valid_spendable_coins)
-            assert smallest_coin is not None
-            log.debug(f"Selected closest greater coin due to the large amount of coins. {smallest_coin.name()}")
-            return {smallest_coin}
-
+    if smaller_coin_sum == amount and len(smaller_coins) < 500:
+        log.debug(f"Selected all smaller coins because they equate to an exact match of the target.: {smaller_coins}")
+        return set(smaller_coins)
     elif smaller_coin_sum < amount:
         smallest_coin = select_smallest_coin_over_target(smaller_coins, valid_spendable_coins)
         assert smallest_coin is not None
         log.debug(f"Selected closest greater coin: {smallest_coin.name()}")
         return {smallest_coin}
     else:
-        knapsack_coin_set = knapsack_coin_algorithm(smaller_coins, amount, max_coin_amount)
-        assert knapsack_coin_set is not None
-        log.debug(f"Selected coins from knapsack algorithm: {knapsack_coin_set}")
-        return knapsack_coin_set
+        coin_set = knapsack_coin_algorithm(smaller_coins, amount, max_coin_amount)
+        log.debug(f"Selected coins from knapsack algorithm: {coin_set}")
+        if coin_set is None or len(coin_set) > 500:  # lots of dust
+            coin = select_smallest_coin_over_target(smaller_coins, valid_spendable_coins)
+            if coin is None or coin.amount < amount:
+                raise ValueError(
+                    "Can't make this transaction because the transaction would use over 500 "
+                    "coins which is unlikely to get confirmed. Try making a smaller transaction to condense the dust."
+                )
+            else:
+                coin_set = {coin}
+                log.debug(f"Resorted to selecting smallest coin over target due to dust.: {coin_set}")
+        return coin_set
 
 
 # These algorithms were based off of the algorithms in: