If a Partner offers next day delivery for an item they're selling through notonthehighstreet, you’ll be able to see this listed under the delivery options drop down. It’s under the product photo on the left hand-side of the product page. You’ll be able to select it at the final stage of the checkout process.
Please be aware that not all items are available for next day delivery and that next day delivery is not necessarily for the next business day, but usually for the day after your order is dispatched. It also depends on the time you place your order, so to avoid disappointment please contact the Partner by clicking ‘Ask seller’ button to confirm: