Making a Fee Required or On by Default

Two settings decide whether a fee starts ticked, or whether customers get a say at all. Both live in the Behavior card on Settings → Cart Widget: "Control how the toggle checkbox behaves for customers."

Two ways to make a fee less optional

The cart widget adds the fee at the cart's checkout button. Express buttons that skip the cart, such as Buy it now, Shop Pay and PayPal, never pass through it, so neither setting reaches those buyers.

Option 1: Check the box by default

The Behavior card, shown at its defaults. Toggle checkbox decides whether customers get a choice at all; Default toggle state decides how that choice starts out.

1. Go to Settings → Cart Widget
2. Scroll to the Behavior card
3. Leave Toggle checkbox on Enabled — customers can opt in/out
4. Set Default toggle state to Checked (opt-in by default)
5. Save

The widget now paints ticked the first time a customer sees it, using the Default Content title and description. The Dynamic Content opt-in copy is swapped in only when a customer ticks or unticks the box.

The confirmation popup switches on for you

Changing Default toggle state moves Show confirmation popup at checkout to match: Checked (opt-in by default) turns it on, Unchecked (opt-out by default) turns it off again. You can set it back to Disabled afterwards and it will save.

The popup asks customers to confirm their selection, names the charge and the amount, and offers Cancel and Checkout. Cancel stops checkout and returns them to the cart with the box still ticked, so anyone who does not want the fee unticks it there and checks out again.

Option 2: Remove the checkbox entirely

Set Toggle checkbox to Disabled — widget is always active. The checkbox disappears, the fee is added whenever a customer checks out from the cart, and there is no way to decline it. The price stays visible on the widget.

Set the popup before you switch. The other two settings disappear from the card once the toggle is disabled, but they keep their saved values. Set Show confirmation popup at checkout to Disabled first: with no checkbox on screen, Cancel gives the customer nothing to change, and their only way forward is to click checkout again and accept the charge they just declined.

Before you remove the choice

Shopify's guidelines say optional charges must be off by default, with no exception for fees you consider mandatory. Deciding that a charge is not optional, a legally required fee or a deposit for example, is a call you need to be able to defend. For anything a customer could reasonably refuse, keep Toggle checkbox enabled and Default toggle state on Unchecked (opt-out by default): charges added without consent can lead to App Store rejection and chargebacks.

It still shows unchecked when you test it

TackOn remembers each customer's last choice in their browser, and that beats the store default. If you have ever ticked or unticked the widget in the browser you are testing in, it keeps its own state. Test in a private window, or clear your storefront's site data. For other widget symptoms, see Scheduling, Visibility & Troubleshooting.

Going deeper

For the behaviour settings in context, with the Dynamic Content opt-in and opt-out copy pairs and the full customiser walkthrough, see Designing the Cart Widget.