Pos Indonesia provides the postal service in Indonesia. Pos Indonesia is government-owned and offers services ranging from sending letters and packages to money transfers (usually to remote areas which have no bank branch/ATM nearby) and selling postcards and stamps.

It is recommended to send letters from a Pos Indonesia branch, not by putting it inside orange mailbox (called Bis Surat) in the roadside, because some of the mailboxes are in very bad condition and aren't checked regularly by Pos Indonesia. Opening times of post offices usually tend to follow general business hours: Monday to Friday from 8:00am to 4:00pm (sometimes shorter hours on Fridays), Saturdays from 8:00am to 1:00pm, closed on Sundays. Bigger cities, tourist areas and central post offices tend to keep longer hours, into the evenings.
Sending a postcards, letter or parcel is relatively expensive, but fairly reliable. It takes several days at least to send it within Indonesia, at least a week internationally.

Private postal services based in Indonesia include CV Titipan Kilat (CV TIKI), Jalur Nugraha Ekaputra (JNE), Caraka, and RPX. There are also foreign postal services that have branches in Indonesia, including DHL, TNT, UPS, and FedEx.

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