Bitcoin as a Currency

Bitcoin was introduced as a peer-to-peer electronic cash system, so judging it as a currency is not a side issue. It goes to the purpose of the network. The complication is that something can be spendable without becoming the money that households use for wages, merchants use for prices, businesses use for accounts and borrowers use for long-term contracts. Bitcoin has clearly crossed the first threshold. It can be transferred from one holder to another and accepted in payment. The harder question is how completely it performs the broader economic job of money.

The answer is more nuanced than a contest in which Bitcoin either replaces the dollar or fails. National currencies benefit from deep legal, banking and commercial infrastructure, and most people earn, budget and pay taxes in those currencies. Bitcoin operates beside that system rather than outside economics altogether. It has developed a large investment market, a global transfer network and a community of users willing to hold it directly, yet those achievements do not automatically make it a convenient unit for buying groceries, setting salaries or quoting a mortgage.

What it means for Bitcoin to function as currency

Economists usually evaluate money by the work it performs. A useful currency needs to facilitate exchange, provide a reasonably dependable way to carry purchasing power through time and serve as a unit in which prices and obligations can be stated. These functions overlap, but they are not identical. An asset can be valuable and transferable while still being awkward as a unit of account, just as something can be widely quoted in markets without being commonly used at the checkout counter.

Bitcoin is unusual because the asset and the payment network are closely connected. Ownership is represented through entries on a public blockchain, and transfers are authorized with cryptographic keys rather than through an instruction to a commercial bank. The network has protocol-defined rules for issuance and transaction validation, and no central issuer promises to redeem each bitcoin for a fixed amount of dollars, euros or another asset. That distinguishes it from bank deposits, traditional electronic payment balances and stablecoins even though all of them can be used to move value digitally.

Bitcoin also differs from physical commodities even when investors describe it in commodity-like terms. Gold, for example, has a physical form and nonmonetary uses, while bitcoin exists only as a digital asset recorded and transferred through its network. The comparison with precious metals is still useful because both can be held outside the ordinary bank-deposit system and both are sometimes bought as scarce assets rather than because the owner expects to spend them soon. Bitcoin belongs to the wider market of cybercurrencies, now more commonly called cryptocurrencies, but its monetary usefulness has to be judged on its own network, market and adoption rather than inferred from the category name.

The hardest problem is not technology but acceptance

A payment method becomes more useful as more people on the other side of a transaction are prepared to accept it. The U.S. dollar does not need to persuade a typical American employer, supermarket, utility company and tax authority to participate each time it changes hands. The surrounding economy is already organized around dollars. A person paid in dollars can generally spend in dollars without first making an exchange decision, and a merchant that receives dollars can use the same unit for payroll, rent, suppliers, taxes and accounting.

Bitcoin has to overcome that incumbent advantage. A customer who earns dollars but wants to pay in bitcoin must first acquire bitcoin, unless the customer already holds it. A merchant that prices goods in dollars but receives bitcoin then decides whether to keep the bitcoin or convert it back into dollars. Either side may face exchange spreads, service fees or price movement during the period in which bitcoin is held. Those costs can be small in some transactions and significant in others, but the important point is that the extra currency conversion is part of the economic calculation.

Recent U.S. payment data show how large the adoption gap remains. Federal Reserve Bank of Kansas City researchers, using the Federal Reserve Board’s Survey of Household Economics and Decisionmaking, reported that the share of U.S. consumers who used cryptocurrency for payments fell from nearly 3 percent in 2021 and 2022 to less than 2 percent in 2023 and 2024. The measure covers cryptocurrency broadly rather than Bitcoin alone, so it should not be read as a Bitcoin market-share statistic. It does show that cryptocurrency payment use remained a small part of consumer activity even after years of greater public awareness.^[1]

Volatility makes everyday pricing awkward

Exchange-rate volatility matters more to a Bitcoin user than it does to someone who earns and spends in one national currency. A coffee priced at five dollars is still five dollars a few minutes later even if the dollar has moved slightly against the euro or yen. If the merchant thinks in dollars but accepts bitcoin, the number of satoshis required for that purchase changes with the bitcoin-dollar exchange rate. Payment processors can calculate that conversion instantly, but they do not remove the underlying fact that the merchant’s economic price is still being set in dollars.

The same issue affects the buyer. Someone who views bitcoin primarily as a long-term asset may hesitate to spend it after a sharp price decline because doing so locks in a lower dollar value, or may hesitate after a sharp rise because the holder expects further appreciation. Ordinary money works best when users do not have to make an investment decision every time they pay a bill. Bitcoin’s volatility does not prevent payment, but it can turn a routine purchase into a choice about portfolio exposure.

The unit-of-account problem is a deeper test

Merchant acceptance alone can overstate how currency-like Bitcoin has become. A business may advertise that it accepts bitcoin while continuing to set every price in dollars and using a payment provider that converts the proceeds immediately. The customer has made a Bitcoin payment, but the economic system underneath the sale still uses the dollar as its unit of account. Prices, wages, taxes and the merchant’s profit calculation remain anchored to national currency.

A more complete monetary transition would look different. Businesses would quote stable bitcoin prices without continuously translating from dollars, workers would be comfortable negotiating compensation in bitcoin, and long-term contracts would be written in bitcoin without both sides feeling that they had taken an additional speculative position. That standard is demanding, but it explains why payment acceptance and currency adoption should not be treated as synonyms.

How Bitcoin payments actually work

On the base Bitcoin network, a transaction is broadcast to the network and can be included in a block through mining. Once it has been included, additional blocks add further confirmation. The process gives Bitcoin a way to transfer ownership without asking a central bank, card network or commercial bank to maintain the authoritative ledger. It also means that settlement works differently from a card authorization that appears almost instantly on a merchant terminal but may involve several institutions and later settlement behind the scenes.

For a low-risk retail payment, a merchant does not necessarily need to wait for the same degree of confirmation that would be sensible for a very large transfer, but accepting an unconfirmed or lightly confirmed transaction involves a different risk decision. Base-layer capacity is finite and transaction fees are market-driven, so periods of heavy demand can make on-chain settlement more expensive or less convenient for small purchases. Technologies built around Bitcoin, including payment channels and the Lightning Network, are intended to move many transactions away from the base layer and settle net results back to it, which can make smaller payments faster and cheaper.

Layered payments improve the practical case for Bitcoin, but they also change the user experience. A consumer may rely on a wallet provider, exchange, Lightning service or payment processor even though the underlying Bitcoin protocol is decentralized. That is not a contradiction. A decentralized settlement asset can support centralized and semi-centralized services at the edges because many users prefer convenience, account recovery and simple interfaces to managing every technical detail themselves.

The distinction between self-custody and custodial use matters for risk as well. A self-custody user controls the private keys needed to authorize spending, which reduces dependence on a financial intermediary but makes key security and backup the user’s responsibility. A customer who leaves bitcoin with an exchange or payment app gets a more familiar account experience but takes exposure to that service provider. The ability to transfer bitcoin without a bank does not mean every Bitcoin payment is made without an intermediary.

Bitcoin is also better described as pseudonymous than anonymous. The blockchain records transactions publicly under addresses rather than personal names, and an address does not by itself identify its owner. Once an address is linked to a person or business through an exchange account, a merchant record, public disclosure or investigative work, blockchain history can reveal connected activity. The old idea that Bitcoin payments are automatically hidden from governments or other observers therefore misstates how the system works.

U.S. tax treatment adds friction to everyday spending

For a U.S. taxpayer, spending bitcoin can have a tax consequence that paying with dollars ordinarily does not. The IRS treats digital assets as property rather than currency for federal tax purposes. A taxpayer who uses bitcoin to buy goods or services has disposed of a digital asset, and the transaction can produce a capital gain or loss when the bitcoin was held as a capital asset. The IRS also requires records sufficient to support basis, fair market value and the resulting tax treatment.^[2]

Suppose a buyer acquired bitcoin for $500 and later spends that same amount of bitcoin when its market value has risen to $700. Economically, the buyer has paid $700 for the purchase, but for U.S. tax purposes the transaction can also represent a $200 gain on the bitcoin that was disposed of, subject to the taxpayer’s facts and applicable rules. If the bitcoin had fallen to $400, a loss could arise instead, although the treatment and deductibility of losses depend on how the asset was held and the taxpayer’s circumstances.

Recordkeeping software and custodial platforms can reduce the administrative burden, but they do not make the property classification disappear. Frequent small purchases potentially create frequent disposition records. That does not make Bitcoin unusable as money, and tax rules vary by jurisdiction, but it is a practical reason why a U.S. resident may find dollars simpler for ordinary spending even when a merchant readily accepts bitcoin.

Merchants face their own accounting choices. A business that accepts bitcoin must determine the value of what it received and then account for what happens if it keeps the asset rather than converting it immediately. A merchant that wants payment exposure without bitcoin price exposure can use a processor that converts the proceeds, while a business that retains bitcoin is making a separate treasury decision after the sale. The payment function and the investment decision should be analyzed separately even when they occur in the same transaction.

Bitcoin’s investment role has grown faster than its payment role

The original version of this article recognized an important tension: Bitcoin was designed for payments, but public attention increasingly centered on its market price. That tension has become more pronounced. Periods of exponential growth in Bitcoin’s price drew investors who were interested in appreciation, trading and portfolio exposure rather than in using bitcoin to settle everyday purchases. A liquid investment market can strengthen an asset’s visibility and ease of acquisition without creating the merchant network or price stability associated with ordinary currency.

U.S. market access has also changed materially. In January 2024, the Securities and Exchange Commission approved the listing and trading of a number of spot bitcoin exchange-traded product shares. Those products allow investors to obtain bitcoin price exposure through conventional brokerage accounts without personally managing a wallet or private keys. The approval did not amount to an SEC endorsement of bitcoin, but it marked a clear expansion of the regulated investment channels through which investors could access it.^[3]

For readers familiar with conventional ETFs, the trading experience of spot bitcoin ETP shares can look familiar even though the legal structures and regulatory details are not identical to every registered investment-company ETF. The important point for Bitcoin’s currency role is more basic. Easier securities-market access gives investors another way to hold exposure without ever using the Bitcoin network for a payment, so growth in investment ownership should not be mistaken for equal growth in monetary use.

There is also a behavioral tension between an asset expected to appreciate and a currency intended to circulate. A holder who believes bitcoin will become much more valuable may prefer to spend dollars and keep bitcoin. That decision is individually rational if the expectation proves correct, but widespread hoarding reduces the frequency with which the asset is used as a medium of exchange. An asset can be an effective long-term holding for some investors and a poor day-to-day spending choice for the same people.

Where Bitcoin still works well as a payment asset

Bitcoin’s limitations as an everyday domestic currency should not obscure the situations in which its design is genuinely useful. A holder can transfer value to another compatible wallet without relying on the recipient’s bank to be open, without needing both parties to use the same commercial payment app and without asking a card network to authorize the transfer. The network is global in the sense that the protocol does not assign a different version of bitcoin to each country, although local laws, exchange access and compliance requirements still affect how people acquire and use it.

That feature can matter when the alternative payment path is slow, expensive or unavailable. Cross-border transfers, settlement between parties that already hold bitcoin and payments to merchants that actively want bitcoin are more natural use cases than forcing every domestic purchase through a cryptocurrency conversion. The advantage is strongest when Bitcoin removes a real friction from the existing payment route rather than when it simply replaces a fast local payment with an extra conversion step.

Self-custody is another distinctive feature. A person who holds private keys can control the ability to transfer the asset without depending on a bank account balance being updated by a third party. That autonomy carries operational risk because losing access to the keys can mean losing access to the bitcoin, and there is no universal chargeback mechanism comparable with consumer card protections. Users who value direct control may accept that responsibility, while others will rationally prefer intermediated services.

Bitcoin can also serve as a fallback monetary asset in circumstances where confidence in a local currency or financial system is weak. The case should not be overstated. A volatile asset introduces its own uncertainty, internet and device access can become constraints, and governments can regulate exchanges and commercial use even if they cannot rewrite the Bitcoin ledger unilaterally. Still, an asset that can be held and transferred independently of a local bank can have more monetary utility in a stressed financial environment than it does in a country with stable money and efficient payment rails.

What would need to change for Bitcoin to become a more common currency

Wider currency use would require improvements on several fronts at once rather than one decisive technical breakthrough. Payment infrastructure has to make small transactions cheap and fast enough for ordinary commerce, while users need wallets and services that are understandable without sacrificing the features they value in Bitcoin. Merchants need confidence that accepting the payment will not create disproportionate accounting, fraud or conversion costs. Consumers need a reason to choose Bitcoin over cards, bank transfers, instant-payment systems and other digital options that already work well in many markets.

Price behavior is harder to engineer. A currency becomes easier to use when households and businesses have reasonable confidence about its near-term purchasing power, because they do not have to protect every transaction against large exchange movements. Greater market depth and broader ownership could reduce some forms of volatility over time, but there is no rule that guarantees Bitcoin will become stable enough to be a routine unit of account. Its fixed-supply narrative and investment demand can continue to make price expectations central to why people hold it.

Tax and regulatory treatment can also influence behavior. If using an asset for a small purchase creates recordkeeping that does not arise when spending national currency, the consumer starts with a practical disadvantage. Changes in tax rules could alter that calculation, but the current U.S. framework still treats digital assets as property. Outside the United States, different legal and tax systems can produce different incentives, which is another reason not to make a universal claim about Bitcoin’s suitability as currency.

The most difficult hurdle may be network effects rather than code. People prefer money that other people already accept, businesses prefer the unit their customers and suppliers already use, and contracts are easier to write in the unit used for accounting and taxes. Bitcoin does not have to displace that entire structure to succeed as a payment asset, but becoming the primary currency of a large developed economy would require a much deeper shift in wages, prices, liabilities and commercial habits than adding a Bitcoin button to an online checkout.

Bitcoin can be money in some contexts without replacing national currencies

Calling Bitcoin a currency is defensible when the word means a transferable asset that people voluntarily accept in payment. It is less persuasive if currency is taken to mean the dominant unit in which an economy prices goods, pays wages, records debts and settles taxes. Bitcoin performs the medium-of-exchange function in a real but limited set of transactions, offers a distinctive form of self-custodied digital value and has developed far beyond the experimental stage as an asset. Its role as a general unit of account remains much weaker.

The better question is therefore not whether Bitcoin is “really” a currency in an all-or-nothing sense. It is which monetary functions it performs well, for whom and at what cost. In the United States today, its investment and store-of-value use cases are more developed than its role in routine consumer payments, and national currency still provides the default unit for prices, income and taxation. Bitcoin does not need to overthrow that system to remain economically important. It can continue to operate as a global digital asset and specialized payment network, with its currency role expanding where the advantages of direct transfer outweigh volatility, tax friction and the convenience of established payment methods.