Shopify is about to pick for you, and most merchants still could not tell you what it picked.
DDU and DDP are the two ways a cross-border customer meets the import duty on their order. DDU, Delivered Duty Unpaid, means the duty is not in your checkout. It turns up later, when the courier knocks and asks for it on the doorstep. DDP, Delivered Duty Paid, means the duty is collected at the checkout, folded into the total, and the parcel arrives with nothing left to pay.
Here is the decision, without the jargon.
Choose DDP when your orders carry real duty and your customer would hate a surprise. Higher order values, markets with proper import charges, anything where a doorstep bill would feel like a betrayal. DDP kills the worst moment in cross-border retail, the refused parcel and the one-star review that rides in behind it. The cost is honesty. Your checkout total goes up, in plain sight, and some carts will wobble at the bigger number.
Choose DDU only when the surprise is small. Low order values, low or zero duty markets, customers who genuinely expect to settle on delivery. Here a lower checkout number wins more add-to-carts than the occasional doorstep grumble loses. Pick it on purpose, not by accident.
For most stores selling real product across a real border, DDP is the right call, because the doorstep is where cross-border orders go to die. But it is not free. The moment you switch, watch add-to-cart to purchase, because you have just changed your price in every affected market on the same day.
The real question is not DDU or DDP. It is where you want the customer to meet the duty. In your checkout, where you can see it and price for it, or on their doorstep, where you cannot.
If this is the call you are weighing before the 24th, tell me your markets and order values: mail@sandeepkv.com, or message me on LinkedIn.