The invention relates to a data transfer method in a digital cellular radio network, the method comprising channel coding the information to be transferred for transmission. In order to implement a data rate of 14.4 kbit/s in GSM type of cellular radio systems by employing one time slot only for data transmission, the channel coding according to the method of the invention comprises grouping bits to be transmitted in blocks having the minimum size of 288 bits, carrying out convolutional coding for the blocks with a code rate of 1/2 by using GSM convolutional coding polynomes, and puncturing the bits obtained by deleting bits from each block so that blocks containing no more than 456 bits will be obtained.