What’s the best way to transfer money from the U.S. to Pakistan?

Wire transfers typically take 2-3 business days to execute and settle, and in some cases can be done in one day as well. Settlement into an account can be up to 3-5 days in total. However, banks do like to keep the float on your incoming US Dollar for a day or two, so depending where you bank, it can be up to 7 days.

It is very important to understand that many US banks do not have a direct relationship with Pakistani Banks, and hence a intermediary (or Correspondent) Bank is used. So if you are transferring money from say Sunbank (US) to Silk Bank (Pakistan), Sunbank will hop onto the SWIFT system and see that they have a number of options for correspondent banking. They would most likely use Standard Chartered Bank and move the funds through them, and SCB US will settle with SCB Pakistan and then settle the funds into your Silk Bank account.

All banks today use Society for Worldwide Interbank Financial Telecommunication (SWIFT) for Bank transfers internationally.

I answered something similar relating to your question at: How long it takes for an International wire transfer to reach my Standard Chartered Pakistan Rupee Bank Account?

Some points worth noting down:

• There is a State Bank of Pakistan circular (I will have to dig it up) that penalizes your bank for inward money transfer not being credited to your account at the earliest.
• Always try to get a SWIFT MT-103/MT-103+ confirmation from the Sending banking (also known as the Remitting Bank). The MT-103 confirms that the funds were sent and did not have any issue (wrong name, bank name not found, etc.) and present the MT-103 to the receiving bank to quickly trace your wire.
• Do not rely on your Branch to inform you for the Incoming Wire. Try to get the name and number of the person concerned in the Bank's HQ (usually in a department called International Wire Transfers). They can very quickly look up the wire for you, based on MT-103.
• You can learn more about these codes at: http://www.swift.com/resources/d...
• There is a Banking Ombudsman in Pakistan - (Banking Mohtasib) - http://www.bankingmohtasib.gov.pk/ - there website seems to be blank right now, but that is one avenue of registering your complaint, should your wire transfers be delayed.
• Most of the time Wire Transfers go bad because of the Beneficiary Banking instructions are misinterpreted. Always try to send these instructions in Courier format, so there is no confusion between an 0 (Zero) and O (Capital "o"). Double check with your bank on the instructions. When in doubt - ask!
• For a bad wire transfer that is not claimed, it can take any where from 7-14 days for the wire to be returned back, minus any mid-bank deduction, which are charges as levied by the correspondent and intervening banks.