diff --git a/src/lib/components/ProductDescriptions/CommaFour.svelte b/src/lib/components/ProductDescriptions/CommaFour.svelte
index e41ec461..121b0846 100644
--- a/src/lib/components/ProductDescriptions/CommaFour.svelte
+++ b/src/lib/components/ProductDescriptions/CommaFour.svelte
@@ -11,7 +11,7 @@
   import MoneyBackGuaranteeIcon from "$lib/icons/features/money-back-guarantee.svg?raw";
   import WarrantyIcon from "$lib/icons/features/warranty.svg?raw";
 
-  import { FOUR_PRICE, FOUR_SALE, FOUR_STRIKETHROUGH_PRICE, FOUR_TRADE_IN_CREDIT, NO_HARNESS_DISCOUNT } from '$lib/constants/prices.js';
+  import { FOUR_PRICE, FOUR_SALE, FOUR_STRIKETHROUGH_PRICE, FOUR_TRADE_IN_CREDIT, NO_HARNESS_DISCOUNT, affirmMonthly } from '$lib/constants/prices.js';
   import { NO_HARNESS_OPTION } from '$lib/constants/vehicles.js';
 </script>
 
@@ -61,6 +61,9 @@
   $: priceDueToday = showDiscount ? FOUR_PRICE - NO_HARNESS_DISCOUNT : FOUR_PRICE;
   $: priceAfterTradeIn = tradeInChecked ? priceDueToday - FOUR_TRADE_IN_CREDIT : priceDueToday;
 
+  // Affirm finances what's charged today — the trade-in credit lands after we receive the device
+  $: affirmPrice = affirmMonthly(priceDueToday);
+
   $: additionalProductIds = (() => {
     const ids = [];
     if (selectedHarness && selectedHarness !== NO_HARNESS_OPTION) {
@@ -142,6 +145,16 @@
   </div>
 
   <span slot="price-accessory">
+    <div class="financing">
+      or ${affirmPrice}/mo with Affirm.
+      <a
+        href="https://www.affirm.com/apps/prequal/?public_api_key=EE7S5PMJUQ8H98C5&amp;device_id=063366d6-31b6-4e41-adcb-79f608745058&amp;referring_url=https%253A%252F%252Fcomma.ai%252Fshop%252Fcomma-four&amp;unit_price={priceDueToday}00&amp;page_type=product&amp;use_promo=true&amp;locale=en_US"
+        target="_blank"
+        class="highlight"
+      >
+        Prequalify now
+      </a>
+    </div>
     <div class="badges">
       <Badge style="dark">Free rush shipping</Badge>
       {#if tradeInChecked && FOUR_TRADE_IN_CREDIT > 0}
@@ -244,6 +257,10 @@
     border-bottom: 1px solid rgba(0, 0, 0, 0.15);
   }
 
+  .financing {
+    text-wrap: pretty;
+  }
+
   .badges {
     display: flex;
     flex-wrap: wrap;
diff --git a/src/lib/constants/prices.js b/src/lib/constants/prices.js
index c67736b9..47c832ef 100644
--- a/src/lib/constants/prices.js
+++ b/src/lib/constants/prices.js
@@ -8,3 +8,16 @@ export const FOUR_STRIKETHROUGH_PRICE = null;
 export const FOUR_PRICE = 999;
 export const FOUR_TRADE_IN_CREDIT = 250;
 export const NO_HARNESS_DISCOUNT = 50;
+
+// Affirm's longest term, which is the one we advertise since it's the lowest monthly.
+// Verified against affirm.com's own calculator at $699/$749/$949/$999 — same term and
+// rate across the range, so the monthly scales with the price.
+export const AFFIRM_APR = 0.15;
+export const AFFIRM_TERM_MONTHS = 12;
+
+// Standard amortized payment. Rounded up, so we never advertise less than what Affirm charges.
+export function affirmMonthly(price) {
+  const monthlyRate = AFFIRM_APR / 12;
+  const payment = price * monthlyRate / (1 - Math.pow(1 + monthlyRate, -AFFIRM_TERM_MONTHS));
+  return Math.ceil(payment);
+}
diff --git a/src/routes/shop/comma-four/+page.svelte b/src/routes/shop/comma-four/+page.svelte
index 1f0e14fe..a54e3868 100644
--- a/src/routes/shop/comma-four/+page.svelte
+++ b/src/routes/shop/comma-four/+page.svelte
@@ -306,6 +306,12 @@
             International shipping is a $30 flat rate; customs/duties/taxes are between you and your country.
             Please see FAQ for more information.
           </p>
+          <strong>Affirm</strong>
+          <p>
+            Your rate will be based on credit, and is subject to an eligibility check.
+            Payment options through Affirm are provided by these lending partners: <a href="http://affirm.com/lenders" target="_blank" class="highlight">affirm.com/lenders</a>.
+            Options depend on your purchase amount, and a down payment may be required.
+          </p>
           <strong>Warranty</strong>
           <p>
             1-year limited warranty against hardware defects. Extend it with <a href="/connect#what-is-commacare" class="highlight">commacare</a>. Open and repair the comma four at your own risk.