STATEFUL LAYERED CHAIN MODEL TO IMPROVE THE SCALABILITY OF BITCOIN 10.5455/jjcit.71-1674157604 Dalia Elwi,Osama Abu-Elnasr,A. S. Tolba,Samir Elmougy Bitcoin,Cryptocurrency,Blockchain,Stateful,Layered,Chain,Scalability,Storage,Throughput 1359 337 19-Jan.-2023 26-Mar.-2023 1-Apr.-2023 Bitcoin becomes the focus of scientific research in the modern era. Blockchain is the underlying technology of Bitcoin because of its decentralization, transparency, trust-less and immutability features. However, blockchain can be considered the cause of Bitcoin scalability issues, especially storage. Nodes in the Bitcoin network need to store the full blockchain to validate transactions. Over time, the blockchain size will be bulky. So, the full nodes will prefer to leave the network. This leads to the blockchain being centralized and trusted and the security will be adversely affected. This paper proposes a Stateful Layered Chain Model based on storing accounts’ balances to reduce the Bitcoin blockchain size. This model changes the structure of the traditional blockchain from blocks to layers. The experimental results demonstrated that the proposed model reduces the blockchain size by about 50.6 %. Implicitly, the transaction throughput can also be doubled.