diff --git a/packages/wallet-webui/src/routes/App.tsx b/packages/wallet-webui/src/routes/App.tsx
index e649abaf4..57ca4883a 100644
--- a/packages/wallet-webui/src/routes/App.tsx
+++ b/packages/wallet-webui/src/routes/App.tsx
@@ -4889,6 +4889,7 @@ function PaymentDialog(props: {
       summary={review.summary}
       order={review.order}
       minimumAge={review.minimumAge}
+      payDeadline={review.payDeadline}
       choices={review.choices}
       selectedChoice={activeChoice}
       error={error}
diff --git a/packages/wallet-webui/src/routes/payment-model.ts b/packages/wallet-webui/src/routes/payment-model.ts
index 8629cf90f..09b8db19d 100644
--- a/packages/wallet-webui/src/routes/payment-model.ts
+++ b/packages/wallet-webui/src/routes/payment-model.ts
@@ -31,6 +31,8 @@ export interface PaymentReviewView {
   summary: string;
   order: OrderSummaryView;
   minimumAge?: number;
+  /** Payment deadline in milliseconds since the epoch, if any. */
+  payDeadline?: number;
   fulfillmentMessage?: string;
   fulfillmentUrl?: string;
   choices: PaymentChoiceView[];
@@ -270,6 +272,9 @@ export function paymentReviewView(
       Amounts.parse(choices[0]?.amountRaw ?? "")?.currency,
     ),
     ...(terms.minimum_age ? { minimumAge: terms.minimum_age } : {}),
+    ...(typeof terms.pay_deadline?.t_s === "number"
+      ? { payDeadline: terms.pay_deadline.t_s * 1000 }
+      : {}),
     ...(terms.fulfillment_message
       ? { fulfillmentMessage: terms.fulfillment_message }
       : {}),
diff --git a/packages/wallet-webui/src/screens/PaymentScreen.tsx b/packages/wallet-webui/src/screens/PaymentScreen.tsx
index da04c0f71..baaf4a407 100644
--- a/packages/wallet-webui/src/screens/PaymentScreen.tsx
+++ b/packages/wallet-webui/src/screens/PaymentScreen.tsx
@@ -7,7 +7,7 @@ import type { ErrorPresentation } from "../ui/error.js";
 import type { PaymentInsufficientBalanceDetails } from "@gnu-taler/taler-util";
 import { ConfirmationDialog } from "../ui/ConfirmationDialog.js";
 import { QrFrame } from "../ui/QrFrame.js";
-import { useState } from "preact/hooks";
+import { useEffect, useState } from "preact/hooks";
 
 export interface PaymentChoiceView {
   index: number;
@@ -163,8 +163,37 @@ export type PaymentScreenState =
   | "done"
   | "error";
 
+/** Payments due within this time show a countdown, as in the iOS wallet. */
+const TIME_TO_PAY_WARNING_MS = 5 * 60 * 1000;
+
+function TimeToPay(props: { deadline: number }) {
+  const [now, setNow] = useState(() => Date.now());
+  const remaining = props.deadline - now;
+  const visible = remaining <= TIME_TO_PAY_WARNING_MS;
+  useEffect(() => {
+    if (remaining <= 0) return;
+    const timer = window.setTimeout(
+      () => setNow(Date.now()),
+      visible ? 1000 : remaining - TIME_TO_PAY_WARNING_MS,
+    );
+    return () => window.clearTimeout(timer);
+  }, [now, remaining, visible]);
+  if (!visible) return null;
+  const seconds = Math.max(0, Math.ceil(remaining / 1000));
+  const time = `${Math.floor(seconds / 60)}:${String(seconds % 60).padStart(2, "0")}`;
+  return (
+    <p role="timer" class="text-right text-sm font-medium text-onWarningContainer">
+      {
+        // Translators: Placeholder is the remaining time (minutes:seconds) before the merchant's payment deadline.
+        i18n.str`Time to pay: ${time}`
+      }
+    </p>
+  );
+}
+
 export function PaymentOptions(props: {
   state: "ready" | "paying";
+  payDeadline?: number;
   choices?: PaymentChoiceView[];
   selectedChoice?: number;
   useDonau?: boolean;
@@ -321,6 +350,9 @@ export function PaymentOptions(props: {
             : i18n.str`Preparing the payment for another wallet…`}
         </p>
       )}
+      {props.payDeadline !== undefined && (
+        <TimeToPay deadline={props.payDeadline} />
+      )}
       <div class="flex flex-wrap justify-end gap-3 border-t border-outlineVariant pt-5">
         {props.onUnclaim && (
           <Button
@@ -442,6 +474,7 @@ export function PaymentScreen(props: {
   summary?: string;
   order?: OrderSummaryView;
   minimumAge?: number;
+  payDeadline?: number;
   choices?: PaymentChoiceView[];
   selectedChoice?: number;
   error?: ErrorPresentation;
@@ -591,6 +624,7 @@ export function PaymentScreen(props: {
           />
           <PaymentOptions
             state={props.state}
+            payDeadline={props.payDeadline}
             choices={props.choices}
             selectedChoice={props.selectedChoice}
             useDonau={props.useDonau}