Calling card suppliers know this and try to hide the cost of the phone call in charges other than the call rate. These charges all add up to make the cost of the phone call breakeven after an average length phone call.

Some of the more common ways of hiding calling costs are:

• surcharges
• peak rate call charges
• monthly charges and weekly or daily maintenance or service fees
• quick expiry
• automatic recharge
• frequent or timed disconnections
• large billing increments
• credit card transaction fees

The surcharges are not the same as a connection or flag-fall fee. A surcharge is generally related to the length of a call and charged at a set time interval after you start speaking, so for example after 5 or 10 minutes a fee of 40c may be charged. This is because not everybody's call is an average length and so the surcharge fee recovers the money for the cheaper call rate. This surcharge can vary depending on the destination you are calling.

If you buy a phone card based on off-peak rates it means it is only really the best card for you during the off-peak period. Most often these off-peak periods are the most inconvenient time of day like 3 am. They are cheaper because the phone card supplier can buy minutes cheaper when no one wants them. You should always buy your caling card based on comparing the peak call rates. That way you are buying the cheapest phone card for when you will actually be using it.

Some calling cards apply a daily, weekly or monthly service fee that eats away at your credit even when you are not using the phone card. With these phone cards it is better to buy the smaller denominations like $5 or $10 and use the whole phone card in one or two calls.

Phone cards have a life lasting from 1 to 12 months. After this they expire and any credit remaining unused on the phone card is lost. The average life of a phone card is 3 months. Any phone cards with a very short life of less than one month should be avoided.

You should be sure to check that your phone card is for a single purchase and that it doesn't automatically charge your credit card again when it is empty to top up or replenish the minutes on the phone card.

If your phone calls drop out after a certain time and this is at the same point each time it probably has a call duration limit. These are often set to 1 or 2 hours. If they frequently drop out at random times this is due to poor line quality. Limited call durations are not only inconvenient but can be very costly if a fixed call duration is combined with high connection fees. You keep getting disconnected and when you redial you are charged another connection fee.

Usually phone cards are billed in one minute increments. This means that if you talk for two and a half minutes you will be charged for 3 minutes. Your standard telecom landline service is generally billed in 1 or 6 sec increments. Some cards bill in 10 minutes increments which means you need to talk for 10, 20 or 30 minutes to get the best value from the card. If, for example, you talked for 13 minutes your call would be rounded up and you would still be charged for 20 minutes!

Make sure you are not charged a transaction fee when you buy your card using a credit card. Sometimes you only see this on your credit card statement a month later. It will generally be about an additional 2% fee to recover the merchant processing fees the bank charges the phone card supplier for using their processing facilities.

To choose the right phone card and be informed of these hazards you need all your phone cards compared and reviewed on the same basis. Ephonecards provides this service free for the most reliable phone cards in Australia.

Another danger you must be aware of is that if you loose your phone card the company will not replace it. This is because someone else can find it and use the remaining balance. You should keep a record of the PIN number in a safe place in addition to details printed on the actual card. With online suppliers like www.ephonecards.com.au your PIN numbers are kept online in your account as well as being sent to you by email so you always have access to the PIN even if you loose it.