It is described a method for certifying data containing a sequence of transactions comprising the following steps:

• finding a new transaction added to the sequence;
• computing a certification code for the new transaction taking into consideration all data preceding the transaction in the preserved order;
• saving the computed certification codes.

In particular, each transaction will carry a certification code and a sequence number that uniquely identify all the data received up to the transaction. By saving the progressive transaction count and the relative certification code it become possible, at a later time, to verify the integrity of the whole data. The described certification method allows the use of electronic certification in the accounting world.