Sending and Receiving Bitcoin

Your first Bitcoin send feels different. The finger hovers. You hit confirm anyway, and the coin is gone whether you meant it or not. No bank picks up the phone. No clawback. The chain settles, and you settle with it.

I send Bitcoin most weeks, and the only reason I stopped checking the address three times is that I built habits that check it for me. This chapter teaches you those habits.

What is a Bitcoin Address?

You generate Bitcoin addresses yourself. Your wallet derives them from your private key with math, not from a bank ledger. That distinction matters more than it sounds.

Addresses look like strings of letters and numbers. The current format starts with bc1q or bc1p, for example bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq. Older formats starting with 1 or 3 still work.

Treat each address as single-use. Coins sent to a reused address still arrive, so this is privacy hygiene rather than a protocol rule. Reuse an address and anyone watching the chain can read every payment that ever touched it: amounts, timing, counterparties. Use a fresh one each time and you make that surveillance much harder. Modern wallets do this for you by default.

To receive, you copy a fresh address from your wallet and hand it to the sender. They paste it, sign, broadcast, and the coin is on its way.

How to Send Bitcoin

A modern wallet send takes six steps. None of them are hard. One of them is where people lose money.

Step 1. Open the wallet and tap Send. Every wallet labels it slightly differently. You will find it.

Step 2. Enter the recipient address. Three ways: type it, paste it, or scan a QR code. Never type. The string is long, easy to fat-finger, and a typo sends your coin to nobody. Pasting is fine if you verify the paste. Scanning a QR code is best because the camera does not make typos.

Step 3. Enter the amount. Most wallets accept BTC, satoshis, or your local currency. Type 50 CHF and the wallet converts at the live rate.

Step 4. Pick a fee. Your wallet offers slow, standard, or fast. The next section explains what these mean. For most sends, standard is right.

Step 5. Review. Read the address again. Read the amount again. Read the fee again. At minimum compare the first four and last four characters of the address against the version the recipient gave you. This is the step that saves your money. Do not skip it.

Step 6. Sign and broadcast. The wallet signs with your private key and pushes the transaction to the network. It hits the mempool within seconds. Depending on the fee you paid, a miner confirms it in the next block or the next few blocks.

Understanding UTXOs

Bitcoin does not store your balance as a number. It stores Unspent Transaction Outputs, or UTXOs. Your balance is the sum of them.

Picture banknotes in a physical wallet. If you received 0.05 BTC, 0.03 BTC, and 0.02 BTC in three separate payments, you hold three notes. Total: 0.10 BTC. Composition: three pieces.

Sending one of these requires picking notes to spend. To send 0.06 BTC when you only hold a single 0.10 BTC UTXO, the wallet spends the whole thing. 0.06 BTC goes to the recipient. A bit goes to the miner. The rest comes back to you as change.

To send 0.04 BTC when you hold 0.03 BTC and 0.02 BTC, the wallet combines both notes, pays out 0.04 BTC, and returns the rest minus fees.

Your wallet handles this without asking. You do not have to think about UTXOs to send Bitcoin. You should still know the concept, because it explains why your transaction history sometimes shows movement you did not initiate, and why some sends cost more in fees than others.

How Transaction Fees Work

Fees have nothing to do with the amount you send. A 0.001 BTC transaction and a 10 BTC transaction cost the same in fees if they take up the same number of bytes on the chain.

Fees scale with data size. A transaction that spends multiple UTXOs is bigger than one that spends a single UTXO, so it costs more. Bigger transaction, bigger fee.

The fee market is an auction. Block space is fixed at roughly one block every ten minutes. When demand spikes, senders bid higher to get in sooner. When the network is quiet, fees collapse to almost nothing.

In recent years, a typical fee for a standard send has run between USD 0.50 and USD 2.00 outside of demand spikes. Check mempool.space for the live number. During the Ordinals inscription wave in late 2023, and again when Runes launched in April 2024, fees briefly punched through USD 30 to USD 50 per transaction.

For most sends, your wallet's standard fee is fine. If you are not in a hurry, picking the slow fee usually costs you an extra hour or two of waiting, not days. If you are paying a merchant or locking in a price, pay the standard or fast fee and stop thinking about it.

What is a Change Address?

Spending a UTXO larger than the amount you want to send leaves a remainder. That remainder comes back to you. Same idea as handing a clerk a twenty for a seven dollar coffee.

Your wallet routes the change to a fresh address it controls, called a change address. The coin is still yours. Glance at your transaction history and you may see what looks like a payment to an unfamiliar address for a small amount. That is your own change coming home.

Wallets rotate change addresses for the same privacy reason they rotate receive addresses. A reused change address ties your transactions together in a public graph and makes you easy to follow.

Key Safety Habits

The expensive mistakes share a few patterns. So do the habits that prevent them.

Verify the full address, or at minimum the first and last several characters. Clipboard hijacker malware exists for one reason: to swap your copied Bitcoin address for an attacker's address between the copy and the paste. You copy, you paste, and the string in the send field is not the string you copied. Real money has gone this way. Glance at the pasted address every time.

Scan QR codes from sources you trust. In person with a merchant, on a verified site you came to deliberately, sure. Do not scan codes printed on flyers, stuck on poles, or sent to you in a stranger's email.

Send a test transaction to any new address. First time paying a new recipient with a meaningful amount? Send a small one first. Confirm it arrived. Then send the rest. Test sends cost cents. Discovering you have been transmitting to the wrong address costs everything you sent.

Check amounts and units. Bitcoin numbers are small and the decimal place is unforgiving. Type 0.1 BTC when you meant 0.01 BTC and you sent ten times what you intended. Entering the amount in CHF or EUR sidesteps this because the numbers look like the numbers you think in.

Risk Note

Bitcoin transactions are irreversible. A wrong address is a permanent loss. Clipboard malware is real, circulating, and has documented victims. Verify the recipient address before you confirm. This is not paranoia. It is the cost of holding your own money.

Reader Takeaway

• Your wallet generates Bitcoin addresses. Use a fresh one for every incoming payment.
• UTXOs are the notes in your wallet. Spending them works like paying with cash.
• Fees scale with data size, not the amount sent. Higher fee buys faster confirmation.
• Change returns to a new address you control. That is normal.
• Verify the recipient address with your eyes before you confirm.

Chapter Summary

• A Bitcoin address is a string derived from your private key. Share it to receive. Rotate it for privacy.
• Sending Bitcoin means entering address, amount, and fee, then signing and broadcasting. The send takes seconds. The first confirmation takes minutes.
• UTXOs are the building blocks of your balance. You spend notes and get change back, like cash.
• Fees track transaction size, not transaction value. They move with network demand.
• Before any meaningful send, verify the address, check the amount, and test with a small payment when the recipient is new.

References

• Nakamoto, S. Bitcoin: A Peer-to-Peer Electronic Cash System (bitcoin.org)
• Antonopoulos, A. Mastering Bitcoin. O'Reilly
• Narayanan, A. et al. Bitcoin and Cryptocurrency Technologies. Princeton
• Bitcoin.org: Developer Guide on Transactions
• Mempool.space: live fee estimates and transaction tracking