Revenue officers in post offices applied charges to more than 70,000 parcels last year.
An average of €33 was added in tax and duty per parcel.
The figures have been issued by Revenue who reminding shoppers ahead of Christmas that shopping online can have tax and duty implications.
In particular, they are warning alcohol or tobacco products bought online or by mail-order are liable to tax and duty on arrival in the State.
The Revenue is also warning people about counterfeit goods, which are illegal and also possibly dangerous.
The officials reminded people that there are no health and safety standards in the counterfeit business.
Finally they reminded people counterfeit goods are often seized at import or export and you are unlikely to receive a refund from the seller.