Like the others said, it's being held by customs. It's done for two reasons - 1) checking if the goods can be legally imported into Spain, 2) checking to see if there is any duty payable on the items - sometimes if the value of the goods that you've declared on the customs slip on the outside is over a certain value, they will require duty to be paid before they release the package. In either situation they will send your boyfriend a notification slip to tell him what needs to be done (in situation 1 if it can't be imported they will seize the package, in situation 2 they will ask for money).

Something about clearing customs.

That's where anything going into the country in question is inspected to make sure it's legal to ship.

Your package will go to Spain and is delivered to Customs who may or may not inspect the package.

When you shipped the package you had to fill out a Declarations form stating what the package contained and what the value of it was.

Customs will look at the declaration, maybe open it to make sure that what you said it is, is what they find and then they will add their VAT (Value Added Tax) of 21% (as of 9/2012) which your boyfriend will have to pay before he can receive it.

Much like your Christmas gift to his parents, he will have to pay 21% of the value of your gift to him.

In most cases a person where relationships extend into other countries you are better off if each has a PayPal account and then you can transfer money to him and allow him to buy his own gift. He will still likely have to pay a VAT but then he also has the option of buying something where the cash you sent would cover the costs of both. Example, if you send him $100 then he can buy an item costing $82.64 without having to take money out of his own pocket.

That it is waiting for the Customs Service to check that it contains something which is legally allowed into the country. THis came from the USA - they will want to check for drugs, illegal weapons, and tea-party propaganda.

It means that it's in the Spanish Border Agency warehouse waiting for them to decide whether there's anything illegal in there and whether they should charge any import duty.

I sent my boyfriend a package for his birthday its on Monday he lives in Spain. I live in America. I am tracking his package and for about 3 days it says Custom Clearance he was supposed to get it today. At least that's what USPS said. Anyway what does Custom Clearance mean?