This is a Block chain Quick Bit, where we cover the basics of a topic, or product, to help you understand it better. This Quick Bit is intended to help you learn about bitcoin transaction fees. Bitcoin transaction fees are one of the many benefits for consumers and merchants to utilize bitcoin, and is an attractive aspect of the digital currency. Currently bitcoin transaction fees can average to around .04 cents USD (or 0.0001 BTC) per transaction. Bitcoin transactions are in place as an incentive to miners when validating bitcoin blocks. One of the reasons there is a fee is because the larger the transaction data size, the longer and more energy it will take miners to validate the data. Transactions with higher transaction fees tend to be validated faster in the block chain. Conversely, transactions with low or zero transaction fees tend to be validated more slowly, or eventually will get rejected. It is extremely important to note that a transaction may be safely sent without fees if these conditions are met

It is smaller than 1,000 bytes.
All outputs are 0.01 BTC or larger.
Its priority is large enough

based on what I read with the Quick Bit Website..