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Why accept bitcoin

A shop accepting bitcoin directly receives the payment in its own wallet, without a processor taking a percentage or controlling the payout. It also takes responsibility for its keys, network fees and the value of the bitcoin it keeps. Whether this is useful depends on the shop’s customers and costs. OpenBMT does not recommend buying or holding bitcoin as an investment and makes no price prediction.

Processing and network fees

A $20 card sale on Square’s United States Free plan costs $0.67: 2.6% of $20 is $0.52, plus $0.15. At 1,000 such sales a month, that is $670 a month or $8,040 a year, before dispute or payout fees.

Square’s pricing, read on 2026-11-11, lists:

PaymentRate
In person: tap, dip or swipe, Free plan2.6% + 15 cents
In person, Plus plan2.5% + 15 cents
In person, Premium plan2.4% + 15 cents
Keyed in or card on file3.5% + 15 cents
Online or invoice, Free plan3.3% + 30 cents
Card issued outside the United StatesAdditional 1.5%

Stripe’s page, read the same day, lists 2.9% + 30 cents for a domestic online card payment, another 1.5% for an international card and another 1% for currency conversion.

An on-chain payment to an OpenBMT wallet has no processor fee. The customer pays to send it; the shop pays a network fee when it later spends the receipt, cashes out or consolidates receipts. That fee depends on transaction size and the current fee rate rather than the sale amount.

On 2026-11-11, mempool.space listed a fastest rate of 4 satoshis per virtual byte. A spend from one receipt in the shop’s two-of-three wallet to two outputs, payment and change, is 201 virtual bytes: 804 satoshis at that rate. The size is calculated from the weight rules in BIP 141. Each additional receipt spent adds 104.5 virtual bytes (design section 9).

During a fee spike, spending a small receipt can cost more than it is worth. A shop can set a minimum on-chain sale or use its own Lightning node for small purchases, avoiding a separate on-chain receipt for each sale. Lightning has routing fees: the mempool.space snapshot of 2026-08-30 showed a median channel charge of 500 millisatoshi plus 100 parts per million. Check https://mempool.space/ for current rates. Getting paid describes both options.

Disputes and refunds

Card disputes can reach well beyond the day of sale. The Visa Core Rules, 24 October 2026 edition, allow a card-fraud dispute up to 120 calendar days after processing. For goods or services not received, the period runs from expected delivery and ends no later than 540 days after the transaction.

Stripe charges $15 when a dispute arrives and retains it even if the merchant wins. Countering costs another $15, returned only on a win. The disputed amount is held for the process, which Stripe says can take 2 to 3 months. Square lists no dispute fee, but holds the funds immediately and keeps its processing fee when the payer wins.

A payer or bank cannot pull back a bitcoin payment confirmed in a block. A refund requires the shop to send a new payment. A chain reversal remains possible, becoming less likely as blocks accumulate; no depth makes it impossible.

Before confirmation, the sender can replace a payment. Above the instant limit, OpenBMT waits for a block. Below it, the shop accepts the risk that a customer could cancel during the roughly ten-minute wait, with the loss bounded by the limit. See Getting paid for the checks and exposure budget.

Payouts and reserves

Card processors can hold funds under their published terms:

  • Square can delay payouts during chargebacks, withhold funds or require a reserve. Its rolling-reserve page names advance payment before delivery, high dispute rates and a lack of processing history as factors.
  • PayPal can place a reserve on a business account at any time. A risk-based hold generally lasts up to 21 days, and a balance can be held for up to 180 days. Its rolling-reserve example holds 10% of payments for 90 days.
  • Stripe says reserve funds cannot be paid out or transferred.

Square’s default payout is the next business day; instant transfer costs 1.95%. Stripe’s standard United States payout is 2 business days after payment; instant payout costs 1.5%.

OpenBMT receives the money in the shop’s wallet. There is no payout to request, and no company holds a wallet key or has a switch to stop receipt. A company cannot freeze that wallet. The shop must keep its own access: losing two keys makes the money unspendable, and approving a bad spend cannot be reversed. The wallet chapter and Operating precautions explain the precautions.

Merchant accounts

A card merchant applies to a processor, supplies identity and bank details, and accepts its terms. The processor decides whether to serve the shop and can later close the account.

OpenBMT needs the shop’s phones and, optionally, a Box. There is no sign-up, identity check or company approval. The shop’s tax, licensing and trade obligations still apply. What OpenBMT will never do explains the account policy.

Supply and price

The Federal Reserve states a goal of “inflation of 2 percent over the longer run”, measured by the personal consumption expenditures price index (read 2026-11-11). At that rate, a dollar held for ten years buys about 18% less: 1 / 1.02^10 = 0.82. Higher inflation would erode it further.

Bitcoin’s block reward began at 50 bitcoin and halves every 210,000 blocks, about four years. Total issuance therefore cannot reach 21 million. Bitcoin Core computes this in GetBlockSubsidy in src/validation.cpp, using the interval in src/kernel/chainparams.cpp. Full nodes reject blocks that pay too much. An operator who keeps the existing rules continues to reject excess issuance; publishing different rules cannot force adoption.

This supply schedule does not stabilize the dollar price. Bitcoin has risen and fallen sharply. A shop holding receipts bears both directions of that movement, and chooses how much to retain or cash out. OpenBMT does not convert the money. Cash-out is an owner-approved transaction to the chosen exchange; its walkthrough will be in the next part.

Running the system

The shop operates its own phones and optional Box, keeping them charged, updated and protected. Small on-chain purchases can be uneconomic; its own Lightning node is an option, but the counter integration has not been tested against a real node. OpenBMT is pre-release and has had no independent audit. Do not use it with real funds.

Fewer customers pay with bitcoin than with cards. OpenBMT makes no claim about adoption numbers. Treat it as an additional payment method when planning for the shop’s customers.

United States tax records

The following is information, not tax advice. Ask a tax professional about your situation. OpenBMT’s accounting export follows United States rules only.

Under IRS Notice 2014-21, Q&A-3 and Q&A-4, bitcoin received for goods or services is income at its dollar fair market value on the day received. That value is also the shop’s basis. The IRS digital-assets page, reviewed 2 September 2026, treats digital assets as property rather than currency. Selling or spending them can create a gain or loss.

Brokers file Form 1099-DA about their customers; a shop does not file it for its own sales. Form 8300 reports cash above $10,000 received in a trade or business. IRS Announcement 2024-4 says digital assets do not count toward that threshold until regulations are published. No final regulation was found on 2026-11-11; check irs.gov for the current rule.

Customers and privacy

A customer holding bitcoin can pay a shop that accepts it. A foreign-issued card carries a foreign-exchange fee; bitcoin has no such fee, while the customer still pays the network fee.

A payment contains no customer name or shop bank details. The wallet description stays on the shop’s devices, and OpenBMT does not give its addresses to a company. Anyone with an address or transaction ID can, however, inspect linked payments on Bitcoin’s public ledger. Privacy describes what the POS vendor and network still see.

Sources

Each page below was read on 2026-11-11.