What if Bitcoin block rewards suddenly stopped tomorrow?

[Patikno]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

I think the use of the word "tomorrow" is inappropriate, it is better to use the word "one day." Because it seems like it will come soon, when what the OP meant was when the mining rewards run out, and that is still a long way off. Regarding your question, I don't think it is possible for Bitcoin to collapse, because we know that there will be many people who will continue to keep the network alive. This is similar to Bitcoin's early launch phase. I believe that during the first to three years of its launch, many people were mining Bitcoin, and perhaps at that time some people still didn't realize Bitcoin's enormous potential, but I'm sure they would still mine it at that day. So I feel that in the future, people will continue to maintain the Bitcoin network, especially if Bitcoin has experienced widespread adoption throughout the world, then I am sure Bitcoin will never collapse.

[pancelot]

It cannot happen because there is a protocol being enforced by the full nodes as part of the decentralized network and in that protocol the block subsidy is clearly defined and it cannot suddenly "stop" without performing a hard fork to change the protocol first. And that's not happening either.

Technically, Bitcoin can't suddenly lose its mining reward without a major protocol change. The block subsidy is embedded in the Bitcoin consensus itself: it decreases by 50% every 210,000 blocks (halving) until it reaches near zero in 2140. You can find the reference here: https://en.bitcoin.it/wiki/Controlled_supply?utm_ This rule is also fully enforced by fullnodes. When a miner creates a block with a different reward, the network automatically rejects it.
Furthermore, in a thread created by Satoshi, who initially designed this incentive to gradually shift from block subsidies to transaction fees, you can also see it here from @satoshi .

Right.  Otherwise we couldn't have a finite limit of 21 million coins, because there would always need to be some minimum reward for generating.  In a few decades when the reward gets too small, the transaction fee will become the main compensation for nodes.  I'm sure that in 20 years there will either be very large transaction volume or no volume.

This is why the Bitcoin consensus is so conservative, making a hard fork to change the reward type virtually impossible.

[EarnOnVictor]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

This ain't happening bro!

The block reward will continue to be divided in half, and miners' rewards will continue to decrease as a result, while the earlier miners will enjoy more. The time of the fee hike will ensure more reward for miners as well. However, the further development (scaling) and adoption of the L2 will be a problem for miners. Though they will still gain, the reward will not be as though it was pushed through the L1 directly.

[henry_of_skalitz]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

This ain't happening bro!

The block reward will continue to be divided in half, and miners' rewards will continue to decrease as a result, while the earlier miners will enjoy more. The time of the fee hike will ensure more reward for miners as well. However, the further development (scaling) and adoption of the L2 will be a problem for miners. Though they will still gain, the reward will not be as though it was pushed through the L1 directly.

Eventually, fees should become bigger than the actual rewards, imo, but these days wouldn't be in our lifetimes, probably.

So miners would still be inclined to continue their honest work.

[btc78]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

theoretically yes if the demand for bitcoin remains and there’s a lot of transactions waiting then yes miners will still be profitable just from transaction fees alone and if miners are happy well then the security remains strong

[fikrett]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

theoretically yes if the demand for bitcoin remains and there’s a lot of transactions waiting then yes miners will still be profitable just from transaction fees alone and if miners are happy well then the security remains strong

I think that interest will always be there for BTC (because it's obvious it's the one to get the most of it), and such a scenario is a speculation anyway if not going forward into the many decades ahead.

[CryptoHeadlineNews]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

Bitcoin is just 16yrs old as a decentralized digital asset, and yet we could all feel the massive and positive impact it has got on global finance, most especially the ability to have full control over our funds without the influence of third parties like the centre bank or government. And as such, I'm pretty sure that before the mining process will end in 2140, which is approximately 105yrs from today, Bitcoin must have adopted to a new technology to allow it function effectively without the mining rewards. Because currently, with the mining BTC reward of 3.125 BTC per block every 10 minutes. In a day, over 450 bitcoins is been mined.

[Asiska02]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

Bitcoin will not collapse. Even without miners getting any more rewards for mining a bitcoin, the reward they will get from the transactions fees of processing bitcoin into the blockchain will be enough for them to continue. Bitcoin will be more scarce by that time, and I’m sure the price of it will be far higher than what it is today, so definitely the miners rewards from transaction fees will be sufficient for them to continue mining. The protocol has been designed to be a continuous process, so I don’t see bitcoin mining coming to  an halt if there are not more bitcoins to mine again.

[krishnaverma]

Without mining rewards, would miners keep the network alive with just transaction fees, or would Bitcoin collapse?

Bitcoin will not collapse. Even without miners getting any more rewards for mining a bitcoin, the reward they will get from the transactions fees of processing bitcoin into the blockchain will be enough for them to continue. Bitcoin will be more scarce by that time, and I’m sure the price of it will be far higher than what it is today, so definitely the miners rewards from transaction fees will be sufficient for them to continue mining. The protocol has been designed to be a continuous process, so I don’t see bitcoin mining coming to  an halt if there are not more bitcoins to mine again.

When there are no bitcoins left to be mined , even then mining will continue ? Really ? When is last bitcoin expected to be mined approx ?

[Donneski]

With the way Bitcoin was designed it's absolutely impossible for block reward to vanish overnight instead, it reduces slowly every four years so that miners and the market have time to adjust. That’s very different from a sudden stoppage of mining rewards.

 If for any reason we experience a sudden stop tomorrow, fees will definitely shoot up as users compete for space in blocks but it still wouldn’t be enough to replace the lost subsidy. Miners would drop out, the network would keep running but with less hash power and overall security will become very weak. Though it's impossible to happen but that's what I don't think anyone in the Bitcoin network will want experience.

[Frankolala]

If it suddenly stops, it will be difficult to sustain mining on transaction fees alone. This would certainly put security at risk and the future of bitcoin would be uncertain. But only time will tell whether it can survive. I don't think that will happen at all. But if it does, the market would be completely destroyed.

Transaction fee will be enough for miners if all bitcoin are mined. Transaction fee will be high in the year 2140 because bitcoin will also be very expensive at that time. Bitcoin network cannot stop because if any miner is not interested anymore due to lack of incentive will pack his bag and leave. Other miners will keep the network going.

[Alone055]

When there are no bitcoins left to be mined , even then mining will continue ? Really ? When is last bitcoin expected to be mined approx ?

The last Bitcoin will be mined in the year 2140, approximately, based on the current speed at which the blocks are being mined, and also based on the halvings that will happen in the future. And yes, mining will still continue even when there are no more Bitcoins to be mined, because there will still be block rewards and transaction fees. The competition might get lower by that time, because if there are no block rewards, there might be a lower number of miners, and when there are fewer miners, they will be able to mine more blocks, and hence, still get enough rewards for their mining activities.

Besides, we don't know what might happen by that time; we are still about 114 years behind that time, and it isn't happening within 2 years, or 5 years, or even a decade. So, I don't think we should be worried about that at the moment; it's better that we focus on other things and let Bitcoin work the way it is supposed to work. If something has to be done in the future, developers will probably do it along with consensus from the miners.

[Cookdata]

If it suddenly stops, it will be difficult to sustain mining on transaction fees alone. This would certainly put security at risk and the future of bitcoin would be uncertain. But only time will tell whether it can survive. I don't think that will happen at all. But if it does, the market would be completely destroyed.

Transaction fee will be enough for miners if all bitcoin are mined. Transaction fee will be high in the year 2140 because bitcoin will also be very expensive at that time. Bitcoin network cannot stop because if any miner is not interested anymore due to lack of incentive will pack his bag and leave. Other miners will keep the network going.

For now it's enough for miners but the more Bitcoin hash rate becomes difficult, more and more sophisticated machines are roll out to miners and this matchines are very expensive. Back then, anyone with their PC could mine Bitcoin which was cheap, with time s9 miners were rollout as the difficulty increases ordinary PC couldn't keep up and people switch to that but again, it's now too difficult to do solo mining unless you joined a pool which makes rewards smaller and work harder.

Unless the cost of producing blocks reduce, mining is going to be difficult by that time but developers are not worried right now because:

-Bitcoin price is increasing which means more money for miners to cover expenses.
-we are still very far from when mining rewards will be too insignificant, many years ahead that many of us might not be alive till then.

For that I believe, they will provide a concensus solution when the time is right about this block reward.