A visa is simply documentation from a foreign country that gives you permission to be in that country for a certain length of time. This differs from a passport in that a passport only represents your home country's permission for you to travel abroad, and officially identifies you in other countries. The requirements differ from country to country; some countries only require you to present a passport to enter their country, while others (like Australia) require you to have a visa in addition to your passport. Foreigners cannot be in Australia without a valid visa.
The type of visa for which you are applying will affect how long it takes to get approval. The most common visa is the Electronic Travel Authority (ETA) visa, a short-term-stay visa available to citizens of an approved list of countries (including the U.S., the United Kingdom and Canada), and can be applied for online. There are also longer-term tourist visas, short- and long-term business visas, student visas and migration visas available. Short-term visas usually process more quickly, while some long-term visas, especially some business visas, take a bit longer.
According to Australia's Department of Immigration and Citizenship, you should allow two to three weeks for a short-term-stay visa to be approved, especially when applying by mail (see References). However, according to the Australian Visa Bureau Web site, most ETA visas receive instant approval when filled out properly online (see References). This applies to both business and tourist ETA visas. Long-term visas (for stays up to 12 months) cannot be filled out online and can take about 10 days to be approved. Some forms of long-term business visas can take a month or more to process, depending on the requirements.
Inevitably, delays happen--even when no one is at fault. Delays with ETA visas usually happen when a traveler did not provide the proper information; this can result in an additional two to five days of processing. Generally, the more complex the process, the more potential there is for delay. Longer-term visas obviously have more documentation and details to consider, so delays could be longer in these cases.
Most delays occur because a traveler did not plan properly. To prevent delays and mishaps, it's best to plan for the unexpected. Know the kind of visa you need, as well as the proper type of documentation you need, before you apply; most Web sites that process visa applications will help you determine what you need. Don't count on instant approval; for ETAs, allow at least an extra week or two. For long-term visas, it's best (when possible) not to finalize your travel plans until you know your visa has been approved. Taking extra precautions up front will prevent many problems later.
