diff --git a/packages/snap-store-mobx/src/Cart/CartStore.test.ts b/packages/snap-store-mobx/src/Cart/CartStore.test.ts
index c5aa9ceab..ff1cb7a6b 100644
--- a/packages/snap-store-mobx/src/Cart/CartStore.test.ts
+++ b/packages/snap-store-mobx/src/Cart/CartStore.test.ts
@@ -91,6 +91,22 @@ describe('CartStore store', () => {
 		expect(cartStore.msrp).toStrictEqual(result.mappings.core?.msrp ? result.mappings.core?.msrp * 3 : 0);
 	});
 
+	it('will ensure price and MSRP are numbers', () => {
+		const cartStore = new CartStore();
+		const result = results[0] as Product;
+		result.quantity = 1;
+
+		// @ts-ignore - sometimes the values in variant data can be strings
+		result.mask.set({ mappings: { core: { msrp: '0.00' } } });
+
+		cartStore.addItems([result]);
+
+		expect(cartStore.items).toHaveLength(1);
+		expect(cartStore.count).toStrictEqual(1);
+		expect(cartStore.price).toStrictEqual(result.mappings.core?.price);
+		expect(cartStore.msrp).toStrictEqual(result.mappings.core?.price);
+	});
+
 	it('can use the eventmanager events', async () => {
 		const cartStore = new CartStore();
 
diff --git a/packages/snap-store-mobx/src/Cart/CartStore.ts b/packages/snap-store-mobx/src/Cart/CartStore.ts
index 7d73634f9..e9bc570c5 100644
--- a/packages/snap-store-mobx/src/Cart/CartStore.ts
+++ b/packages/snap-store-mobx/src/Cart/CartStore.ts
@@ -32,7 +32,7 @@ export class CartStore {
 	get price(): number {
 		let price = 0;
 		this.items.forEach((item) => {
-			price += (item.display.mappings.core?.price || 0) * item.quantity;
+			price += +(item.display.mappings.core?.price || 0) * item.quantity;
 		});
 		return price;
 	}
@@ -40,7 +40,7 @@ export class CartStore {
 	get msrp(): number {
 		let price = 0;
 		this.items.forEach((item) => {
-			price += (item.display.mappings.core?.msrp || item.display.mappings.core?.price || 0) * item.quantity;
+			price += (+(item.display.mappings.core?.msrp || 0) || +(item.display.mappings.core?.price || 0) || 0) * item.quantity;
 		});
 		return price;
 	}