When dialing into Vietnam from another country, replace the leading 0 of any Vietnamese phone number with the country code +84. Vietnamese mobile numbers are typically 10 digits starting with 0 (e.g., 09xx, 07xx, 08xx), while landline numbers also begin with 0 followed by an area code. The trunk prefix 0 is used only for domestic calls within Vietnam and is always dropped for international dialing — this is the standard convention used in most countries worldwide, nothing unusual.
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See all free travel tools →Yes, within Vietnam you keep the leading 0 for all calls — local, long-distance, and mobile. For example, to call a Hanoi landline (024 xxxx xxxx) from Ho Chi Minh City, you dial the full 11-digit number including the 0. Only drop the 0 when calling from outside Vietnam.
Vietnamese mobile numbers are 10 digits long and begin with 0, typically followed by 7x, 8x, or 9x (e.g., 0912 345 678 or 0765 432 100). Different prefixes belong to different carriers such as Viettel, Mobifone, and Vinaphone, but the format is consistent across all of them.
To make an international call from Vietnam, dial 00 (the international access code) followed by the destination country code and the local number. For example, to call a US number, dial 00 1 followed by the area code and number. Many smartphones handle this automatically if you use the + symbol instead of 00.