Currency & denominations
The rupiah (IDR/Rp) comes in large numbers; common notes are Rp1,000, 2,000, 5,000, 10,000, 20,000, 50,000 and 100,000. Prices are sometimes abbreviated (e.g. '50k' for 50,000), so count zeros carefully. The Rp100,000 note is the largest, and breaking it can be hard at small stalls, so keep a mix of smaller notes.
Cash vs card
Cash dominates outside upscale hotels, malls and chain restaurants, especially at warungs, markets, temples and small drivers. Cards are accepted in tourist-heavy areas but often carry a surcharge of a few percent. Always carry enough cash for the day, and keep small notes for parking, tips and street food.
Where to get the best exchange rates
Use only reputable, authorised money changers, ideally those marked as licensed (look for 'PVA Berizin' / Bank Indonesia authorisation) with a clear shopfront and posted rates. Be deeply suspicious of any changer advertising a rate noticeably better than everyone else, as that is the classic bait for short-changing. Banks are safe but offer poorer rates.
Avoid the airport exchange trap
Airport counters in Bali, Jakarta and elsewhere give weak rates; change only a small amount for transport. In town, stick to well-reviewed authorised changers rather than tiny booths down side streets offering 'no commission, best rate'. The combination of a slightly worse airport rate but guaranteed honesty can still beat a too-good-to-be-true street rate.
Using ATMs
ATMs are common in cities and tourist areas; note the per-transaction withdrawal limit (often around Rp1.25-3 million) and check whether the machine dispenses Rp50,000 or Rp100,000 notes. Use ATMs attached to banks or inside malls rather than standalone street machines to reduce skimming risk. Always pay in IDR and cover the keypad when entering your PIN.
Tipping culture
Tipping is not traditional but is increasingly common in tourist areas and genuinely appreciated. Many restaurants add a service charge (often listed as '++' with tax), so check before adding more. For drivers, guides, spa staff and porters, small cash tips are a kind gesture; rounding up is fine elsewhere.
Common money pitfalls & scams
Bali's dishonest changers are infamous for sleight-of-hand: they re-count your money, palm notes, distract you with a calculator, or use rigged drawers, handing back less than agreed. Count your cash yourself, slowly, and do not hand it back once counted; if they recount, count again before you leave. Refuse changers offering implausibly high rates or commission games, and decline dynamic currency conversion on cards.
How much cash should you bring
Plan to use cash daily and withdraw moderate amounts from bank ATMs as you go rather than carrying huge sums. A day's spending on food, transport and entry fees is usually modest, but keep a buffer since ATMs can be down in rural areas and on smaller islands. Always have small notes for tips, parking and warungs.