How big can my box of letters and parcels be? Is there a maximum weight?

Each box of letters and small parcels you send through our Letters and Small Parcels by Whistl drop-off service can weigh up to 20 kg, with a maximum Length + Girth of 3 m. If you’ve booked a collection service, your boxes cannot exceed 20 kg in weight and a maximum length of 1 m. 

Length + Girth is calculated by adding your box’s width and height together, multiplying that number by two, and adding it to the length of your box.

Please note that if one of your boxes exceeds the size limits stated above, you could incur an additional surcharge from the courier that you’ll be required to pay.

For more information on surcharges, click here.

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