Why is there a leftover balance after a sell order?

So, I'm sharing something that's been bothering me while trading (selling my BTC to USDT). I've noticed this consistently in my trades. In the screenshots, you can see that after selling, I have a balance of $0.908 in BTC but on the buy side, I have $118.26. This was after a sell order that came from a total of $120 in BTC. Instead of my BTC balance going to zero, I still have a few cents left, and my buy amount is $118.26, which should have been around $119.5, or $119 minus trading fees. Yet, it still lets me convert that $0.908 worth of BTC to USDT. My issue is with that remaining $0.908 in BTC after I hit max to trade all my BTC. I'm still seeing about 0.00000844 sat left, which is worth like $1. Why is there a leftover balance? Has anyone else run into this while trading on Binance? I might not be using the exact terms, but I hope you get what I'm trying to say.

It is not happening only on Binance, but it is happening on all the exchanges that I am using. That is the reason you will see on some of the exchanges that you can convert the dust coins to the exchange coin like BNB on Binance. You can see that under Assets -> Spot. If you have enough BNB from the dust coins that you converted, you can later convert the BNB to the coin that the want.

Repeatedly it happens to me too always while trading on some exchange and it makes me wonder why it is normally like that, but based on my findings, I understand that every centralized exchange has a minimum set target for the  amount of coins you can sell or buy on the spot trading option. So, if the amount you entered to buy or sell can not contain the additional fractions of the coins you are selling or buying, the order will only be executed for the amount of fraction it can contain. For example, you want to buy $10 worth of Bitcoin, right?  And the Bitcoin equivalent of that $10 is 0.0000929222BTC (with Bitcoin current rate $107, 617) BTC = $107, 617 X 0.0000929222BTC = $10.0000083974 With the above calculation, you can see that the fraction of Bitcoin you are buying is not exactly that $10, therefore what the centralized exchange will do is to accept the only fraction they want. Instead of giving you the above amount, they will put your order as 0.00009BTC (without those micro fractions) which will give you $9.68553. So, after your order executes, you will be left with those 0.0000029....BTC That was not added in the trade. I don't know if you understand my explanation tho. Edit. I didn't know the exact amount of Bitcoin you sold but since you said it was supposed to be $120, I guess it was 0.0011148BTC with the previous rate on your images. The exchange didn't accommodate the micro fractions due to their minimum order amount policy. It same with almost all exchange.

those small leftover amounts are usually dust coins or tiny fraction of your cryptocurrency that remains after a transaction is processed. Even when you try to sell or convert the maximum amount, there can be these minuscule balances left over.  It's a bit like getting a few kobo change after a large purchase, but in crypto, these fractions can be incredibly small.I mostly see this on p2p trades. And since in my country, the government tracks cryptocurrency transactions  using transfers that has a very small fraction which it's unusual for a normal person to transfer, the vendor might simply round down and take the main amount, leaving the dust in your balance or you can choose to leave it on your balance and it looks just like what you are seeing in yours now. So, that $0.908 in BTC is  dust. It's a byproduct of the transaction process, not an error or a significant issue. The fact that Binance still allows you to convert that $0.908 worth of BTC to USDT means it's above their minimum convertible amount for dust, which is a good thing as some exchanges have even higher minimums for dust conversion.

It’s the dust tokens due to the remaining balance is already below the minimum trading value or trading fee. Assuming you do a market order, your total order fill multiple order available in the order book and sometimes a remaining balance is already too small to be traded again. For example you have 50.7$ worth of coins while on order book theres 30$(liquidity volume) - 0.002$(token price) and 20$(liquidity volume) - 0.001$(token price) Therefore you have 0.7$ left on your balance that can’t initiate trading anymore due to low amount less than the minimum trading amount.

You know that most exchanges have the "convert option" And "spot trading option," For the first option, I can covert all the coins (the max amount) I have to the next crypto I want without any micro fractions left behind but on the spot trading option, there's always left overs. Maybe it's different on the exchange you are using since you said you can convert to the max amount.

During a transaction either buy or sell some will be left from the transactions and not all will be consumed. Its normal as it happened with everyone. Oshondy is right, since most cex have option to convert dust tokens we prolly used that to emptied our left over tokens buy those will be converted into their token like in binance it will be converted into bnb automatically.

Dr.Bitcoin_Strange makes a good point. Each trading pair in each exchange has a minimum allowed decimal point. Even if you try to manually type the figure past that decimal point, it won't accept/appear. For example, on Binance, The minimum for BTCUSDT is 0.00001BTC, any figure beyond those five decimals won't be placed in the order book. So if you have your 0.00145364 BTC and you are trying to sell it and even after using that slider that says 100%. On the order book, only 0.00145 BTC will be placed and executed. The remaining 0.00000367 BTC will return to your account as dust amount

Yea, I agree with you mate on everything that you have said. Another thing that can lead to this is also the trading fee. You know that bitcoin price fluctuates, so it might happen that during the time that you clicked on convert, there's a little increase or decrease in price which would make you have a dust amount left.

Be it convert or spot trading on any cryptocurrency you'll always have a minuscule fraction left in your balance even though you use max button. Although what I do observed from many times I have used both options from different exchanges which I don't know if you have observed too. Is that, while you convert the cryptocurrency to another the fees for conversation is usually higher than when you spot trade it to another crypto using the market sell order. And that would be after you have transferred funds from funding wallet to trading wallet in the exchange under "asset". For those that regularly uses exchange like bybit , they would have a better understanding on this

I checked what Dr.Bitcoin_Strange posted now on two exchanges and I noticed he is correct. I checked Bybit and Gate.io. Maybe not on all exchanges but on the two exchanges that I checked now, what he posted is correct.

First, you need to know the minimum conversation amount on that exchange and for that token or coin you want to convert. On binance exchange, the minimum Bitcoin amount you can conver is 0.00000009BTC - 0.92BTC,  so if you have exactly that minimum balance, it will be converted without any more dust left behind but if you have 0.0000000923457BTC and wants to convert to USDT, it's only 0.00000009BTC that will accepted in the transaction  and you will be left with 0.0000000023457 dust again which can never be converted unless you top up. Just this morning, I deposited 0.000272BTC to my binance account and because I didn't want to have a left over dust like OP, I decided not to use the spot trading option, I used the convert option and all my 0.000272 was converted to $29+ without any left over fraction of Bitcoin. About the fees which you talked about, I have compared Bybit conversion fee to binance conversion before, binance is cheaper than Bybit. To compare the fees of "convert option"  And "spot trading option" The difference is not too noticeable on binance exchange unless you took a close look, on bybit it's obvious. I have not made similar comparison on other exchange apart from this two.

This doesn't happen every time because I have sold everything I had on my  exchange and my balance was reflecting that I have nothing left which is zero dollars while other times, there is something left. This is just something that's natural and some exchanges have the options to covert all your small balance that are left from the coins they're in to your desire coin or stable coin coin. This small balances sometimes help us to serve as transaction fees therefore this isn't a problem and your exchange isn't having any issues too. I have experience this on Binance, Kucoin and some other exchanges that I have used.

The order will be executed until it is completed in full. In this case, the balance will be sold when new orders appear at the specified price. The small remaining amounts after the order is closed are part of the amount that is reserved for the trading commission.

I clearly understood what you are saying now, although still that yesterday I was looking for a possible way to see how I can convert it into dollar. What I did was to use the convert feature on the exchange and I also clicked on maximum and it was converted to usdt and now there is no micro balance left on the exchange. Though I have been worried about due  to I wanted to send it to someone and was lucky the exact amount that was needed came from the exchange. And again, where I was lucky enough was their withdrawal fee, if you are withdrawing 20$ above from exchange using BSC there are no charges applied but any amount less than 10$ are charged. I don't also understand why that exchange set it up that way, or could it be since is their network?

I noticed it was binance exchange you used for this transaction. There are a lot of exchanges as you already know and they have different rules, different transaction fee (on spot, convert and futures) and different withdrawal fees depending on the network you are withdrawing from. On binance exchange, they have the Bep20 network and the opBNB network. If you are withdrawing USDT or any token using the Bep20 network, the minimum amount you can withdraw on that network is $10 and from that minimum amount to any max amount you are withdrawing, the fee is $0. If you are using the opBNB network the minimum withdrawal is $20 but fee is still $0. Apart from using bep20 network for the withdrawal, every other network they have such as polygon, ERC20, Aptos, Avax, Tron and TON, all have their minimum withdrawals too and fees are applicable on  those network. For example, the minimum withdrawable amount using Erc20 network is $15. If you are using polygon network the minimum you can withdraw is $0.013usdt and fee is $0.0064 (fee is still cheap). On bybit, as of now, there's no free withdrawal. Every network you are using for your withdrawal has fees but those network still have different minimum withdrawal as well. What I have observed from two different exchange is that withdrawals on Bep20 network is free.

You cannot withdraw any amount that is lower than $10 when you ars using BSC network, and all transaction fees on the network is free. It's same with Bitget exchange. If you are using BSC network in Bitget, you don't pay for any transaction fee. Of course, it's Binance network and they are encouraging people to use it since they control the network. However, in Bybit and Kucoin, you pay at least $0.9 to use BSC network.

It makes me think that this is their way for us to try their coin, or this adds to their coin's volume/liquidity. Even though no loss of money is experienced, I still think this is unethical. Much better if people are only free of what they want to do because that was their money and we already paid them a transaction fee. This may seem not a big deal for a regular or heavy user of an exchange but the dust balance can go a long way already for a small user like me. Also I don't transact that often in a cryptocurrency exchange. I am sure Binance is the ones that does this but they only influenced the other exchange to do the same thing, thinking it is beneficial.

This is common depending on exchanges because some exchanges will make sure that there would be some minor cent remaining on the sellers balance after they finished selling there coin, at first whenever I saw this I usually think that those cent are services charges collected from the transaction the person made but I noticed that those things are not charges but perhaps just a way to make sure that there user wallet will not be entirely empty so that at least there would be some balance left for them even if is not enough to be use for anything, so actually this is not a knew thing.

This also happens to me, I hate it when I see that when I should have fulfilled 100% of the sell order but then, there are dust amounts that remains. It's not a problem though but they keep on doing this because of the reason that they have a feature that we can convert it to their native token. Oshosondy is right about that. That's why before we don't see things like this but now, it's mostly common to all exchanges and that's why don't expect that these dust amounts will be gone. I hate to see them display like that to be honest.