diff --git a/packages/taler-util/src/wallet-types.ts b/packages/taler-util/src/wallet-types.ts
index 41b0d5574..d20eb5173 100644
--- a/packages/taler-util/src/wallet-types.ts
+++ b/packages/taler-util/src/wallet-types.ts
@@ -1134,6 +1134,13 @@ export interface ManualWithdrawalDetails {
    */
   amountEffective: AmountString;
 
+  /**
+   * Number of coins that would be used for withdrawal.
+   * 
+   * The UIs should warn if this number is too high (rougly at >100).
+   */
+  numCoins: number;
+
   /**
    * Ways to pay the exchange.
    */
diff --git a/packages/taler-wallet-core/src/wallet.ts b/packages/taler-wallet-core/src/wallet.ts
index 6009ff096..da9445602 100644
--- a/packages/taler-wallet-core/src/wallet.ts
+++ b/packages/taler-wallet-core/src/wallet.ts
@@ -1107,12 +1107,17 @@ async function dispatchRequestInternal<Op extends WalletApiOperation>(
         Amounts.parseOrThrow(req.amount),
         req.restrictAge,
       );
+      let numCoins = 0;
+      for (const x of wi.selectedDenoms.selectedDenoms) {
+        numCoins += x.count;
+      }
       const resp: ManualWithdrawalDetails = {
         amountRaw: req.amount,
         amountEffective: Amounts.stringify(wi.selectedDenoms.totalCoinValue),
         paytoUris: wi.exchangePaytoUris,
         tosAccepted: wi.termsOfServiceAccepted,
         ageRestrictionOptions: wi.ageRestrictionOptions,
+        numCoins,
       };
       return resp;
     }