Money
The currency is the Indonesian Rupiah (IDR). Notes come in denominations of 1,000 to 100,000 rupiah; the exchange rate fluctuates but is typically around 15,000–16,000 rupiah to the US dollar. Despite the large numbers, Indonesia is not expensive by most international standards — a decent local meal costs Rp20,000–50,000, a motorbike rental Rp70,000–100,000 per day.
Cash is king outside the major cities. ATMs are widely available in cities and tourist areas; carry enough cash when heading to smaller islands or rural areas. Avoid exchanging money at airports — rates are poor. Licensed money changers (penukaran valuta asing) in tourist areas generally offer better rates.
Credit cards are accepted at mid-range and upmarket hotels, restaurants, and shops in Bali, Jakarta, and other large cities, but don't rely on them.
Safety
Indonesia is generally safe for travellers. The main risks are the everyday ones: motorbike accidents (a significant hazard — road conditions and driving standards vary widely), petty theft in crowded tourist areas, and scams targeting new arrivals at airports. Bali's Kuta area is particularly rife with commission-based touts.
Terrorism has been a concern historically — bombings in Bali in 2002 and 2005 and Jakarta in 2003 and 2009. The threat has diminished considerably since then, but the general advice is to stay alert in crowded public places, particularly in the days around major Islamic and national holidays. Check your government's current travel advisories.
The 2004 Indian Ocean tsunami affected the coastlines of Aceh and North Sumatra catastrophically. Those areas have largely rebuilt, but Indonesia sits on the Ring of Fire and earthquakes are common, particularly in Sumatra, Java, and Lombok (which had a serious earthquake in 2018). Understand basic earthquake safety.
Health
The tap water is not safe to drink. Use bottled water or a water purifier; ask hotels and restaurants to use bottled or filtered water for drinks and ice.
Vaccinations: Consult a travel doctor before departure. Most travellers will be advised to ensure they are up to date on hepatitis A, typhoid, and routine vaccinations. Hepatitis B, Japanese encephalitis, and rabies are worth considering depending on where you are going and how long you are staying.
Malaria: The risk varies by region. Bali and most of Java have very low risk. The risk is significant in Papua (Irian Jaya) and parts of eastern Indonesia. Take prophylactics if travelling to high-risk areas and use mosquito repellent and long sleeves at dawn and dusk. Dengue fever is present throughout Indonesia and there is no prophylactic — prevention is about avoiding mosquito bites.
Medical facilities: Good hospitals are available in Jakarta, Bali, Yogyakarta, and Surabaya. Outside major cities, facilities drop off quickly. Comprehensive travel insurance with medical evacuation cover is strongly recommended.
Communications
Indonesia's mobile coverage is good in cities and tourist areas. A local SIM card (Telkomsel has the widest coverage) costs almost nothing and data is cheap — this is the easiest way to stay connected. Gojek and Grab depend on a working local data connection.
Wi-Fi is available at most hotels, cafes, and restaurants in tourist areas.
Language
The national language, Bahasa Indonesia, is straightforward to learn at a basic level. Terima kasih (thank you), tolong (please/help), and berapa? (how much?) will serve you well. English is widely spoken in Bali, Jakarta, and Yogyakarta; much less so in eastern Indonesia and rural areas.
Religion and Customs
Remove shoes before entering homes and temples. Dress modestly when visiting mosques (women should cover hair and arms), and bring a sarong to cover your legs at Hindu temples in Bali — these are usually provided. Public displays of affection are generally disapproved of, particularly outside tourist zones.
During Ramadan, eating, drinking, or smoking in public during daylight hours is considered disrespectful in Muslim-majority areas, though many restaurants in tourist areas stay open.