Block Space Scarcity and the Potential of a Deliverable Forwards Market

As the popularity and usage of Bitcoin have grown, this limited block space has become a critical issue, leading to what is known as block space scarcity.‍

Gabe Higgins
June 3, 2024
Block Space Scarcity and the Potential of a Deliverable Forwards Market

Bitcoin, the world's leading cryptocurrency, operates on a decentralized blockchain network. At the heart of this network are blocks—bundles of transactions that are processed and confirmed by miners. Each block has a finite size, currently capped at four million weight units, which translates to approximately 2,700 transactions per block. As the popularity and usage of Bitcoin have grown, this limited block space has become a critical issue, leading to what is known as block space scarcity.

What is Block Space Scarcity?

Block space scarcity refers to the limited availability of space within Bitcoin blocks to process transactions. With a maximum of approximately 144 blocks mined per day, the Bitcoin network can handle roughly 388,800 transactions daily. This number may seem substantial, but given the increasing global adoption of Bitcoin, it often falls short of the demand, especially during periods of high transaction activity.

Who Does Block Space Scarcity Impact?

Block space scarcity affects several key stakeholders in the Bitcoin ecosystem:

Individual Users: Everyday users who send and receive Bitcoin are directly impacted. When block space is scarce, users must compete to have their transactions included in the next block, often by paying higher transaction fees. This can make using Bitcoin for everyday transactions costly and impractical.

Institutions: Financial institutions, asset managers, and trading firms rely on Bitcoin for various transaction processing needs. Unpredictable transaction fees and potential delays can disrupt their operations, leading to increased costs and financial uncertainty.

Miners: Miners are responsible for confirming transactions and adding them to the blockchain. They earn rewards through newly minted bitcoins and transaction fees. However, fee volatility and competition for block space can create revenue instability, making it challenging for miners to plan their operations and investments.

Developers and Entrepreneurs: Those building applications and services on top of the Bitcoin network face hurdles due to block space scarcity. Higher transaction costs and slower processing times can deter users from engaging with Bitcoin-based services, limiting innovation and adoption.

Problems Caused by Block Space Scarcity

Block space scarcity leads to several significant problems within the Bitcoin ecosystem:

Increased Transaction Fees: As users compete for limited block space, transaction fees rise. This not only makes Bitcoin transactions more expensive but also introduces financial unpredictability, especially for frequent transactors.

Transaction Delays: During peak usage times, transactions can experience significant delays. Users who need their transactions processed quickly must pay even higher fees, exacerbating the cost issue.

Financial Uncertainty for Miners: The volatility in transaction fees impacts miners' revenue streams. As block rewards continue to halve approximately every four years, transaction fees become an increasingly important source of income for miners. Unstable fees make it difficult for miners to plan and sustain their operations.

Barrier to Adoption: High fees and slow transaction times can deter new users and businesses from adopting Bitcoin. This can stifle the growth of the Bitcoin network and limit its potential as a global financial system.

How Forward Markets Work

Forward markets are financial markets that allow participants to enter into contracts to buy or sell an asset at a predetermined future date for a specified price. These contracts are known as forwards and are used primarily to hedge against price volatility. In traditional financial markets, forwards are used for commodities, currencies, and other assets to provide predictability and stability.

The Absence of a Deliverable Forwards Market in Bitcoin

Despite the benefits forwards bring to traditional financial markets, Bitcoin currently lacks a deliverable forwards market for block space. A deliverable forward contract for block space would allow participants to lock in transaction fees and secure block space in advance, providing predictability and stability similar to traditional forwards markets. This could help mitigate the issues caused by block space scarcity, offering a more efficient and reliable transaction processing system.

Potential Benefits of a Block Space Forwards Market

Predictable Transaction Costs: By locking in future transaction fees, users can achieve greater predictability in their financial planning, avoiding the unpredictability of fee spikes.

Stabilized Revenue for Miners: Miners can secure stable income by locking in transaction fees for future blocks, allowing them to better manage their operational costs and investments.

Reduced Transaction Delays: Securing block space in advance can help ensure timely transaction processing, even during periods of high network congestion.

Enhanced Market Efficiency: A forwards market can provide valuable insights into future transaction costs and network conditions, helping all market participants make more informed decisions.


Block space scarcity is a significant issue within the Bitcoin network, impacting users, institutions, miners, and developers. The rising transaction fees and delays caused by this scarcity present challenges that need addressing to ensure the continued growth and adoption of Bitcoin. While Bitcoin currently lacks a deliverable forwards market for block space, introducing such a market could provide the stability and predictability needed to mitigate these issues, benefiting the entire ecosystem. As the Bitcoin network evolves, exploring and developing solutions like a block space forwards market will be crucial for its long-term sustainability and success.