When (if) I should consider cashing in (selling) shares to realize capital gains?
"The only general rule is ""If you would buy the stock at its current price, hold and possibly buy. If you wouldn't, sell and buy something you believe in more strongly."" Note that this rule applies no matter what the stock is doing. And that it leaves out the hard work of evaluating the stock and making those decisions. If you don't know how to do that evaluation to your own satisfaction, you probably shouldn't be buying individual stocks. Which is why I stick with index funds." You should know when to sell your shares before you buy them. This is most easily done by placing a stop loss conditional order at the same time you place your buy order. There are many ways to determine at what level to place your stop losses at. The easiest is to place a trailing stop loss at a percentage below the highest close price, so as the price reaches new highs the trailing stop will rise. If looking for short to medium term gains you might place your trailing stop at 10% below the highest close, whilst if you were looking for more longer term gains you should probably place a 20% trailing stop. Another way to place your stops for short to medium term gains is to keep moving your trailing stop up to just below the last trough in an existing uptrend. "In a perfect world of random stock returns (with a drift) there is no reason to ""take profit"" by exiting a position because there is no reason to think price appreciation will be followed by decline.   In our imperfect world, there are many rules of thumb that occasionally work but if any one of them works consistently over a long period of time, everyone starts to practice that rule and then it stops working.  Therefore, there are no such rules of thumb that work reliably and consistently over long periods of time and are expected to continue doing so.  Finding such a rule is and always has been a moving target. The rational, consistently sensible reasons to sell a stock are: These rules are very different from my interpretation of the ""walk with your chips"" behavior mentioned in your question." How about this rule? Sell 10% of your shares every time they double in price.  (of course, only buy stocks that repeatedly double in price)
Does this make sense? I'm concerned that by buying shares with post tax income, I'll have ended up being taxed twice or have increased my taxable income. ... The company will then re-reimburse me for the difference in stock price between the vesting and the purchase share price. Sure.  Assuming you received a 100-share RSU for shares worth $10, and your marginal tax rate is 30% (all made up numbers), either: or So you're in the same spot either way.  You paid $300 to get $1,000 worth of stock. Taxes are the same as well.  The full value of the RSU will count as income either way, and you'll either pay tax on the gains of the 100 shares in your RSU our you'll pay tax on gains on the 70 shares in your RSU and the 30 shares you bought.  Since they're reimbursing you for any difference the cost basis will be the same (although you might get taxed on the reimbursement, but that should be a relatively small amount). This first year I wanted to keep all of the shares, due to tax reasons and because believe the share price will go up. I don't see how this would make a difference from a tax standpoint. You're going to pay tax on the RSU either way - either in shares or in cash.  how does the value of the shares going up make a difference in tax? Additionally I'm concerned that by doing this I'm going to be hit by my bank for GBP->USD exchange fees, foreign money transfer charges, broker purchase fees etc.  That might be true - if that's the case then you need to decide whether to keep fighting or decide if it's worth the transaction costs. "Once again I offer some sage advice - ""Don't let the tax tail wag the investing dog."" Michael offers an excellent method to decide what to do. Note, he doesn't base the decision on the tax implication.  If you are truly indifferent to holding the stock, taxwise, you might consider selling just the profitable shares if that's enough cash. Then sell shares at a loss each year if you have no other gains. That will let you pay the long term gain rate on the shares sold this year, but offset regular income in years to come. But. I'm hard pressed to believe you are indifferent, and I'd use Michel's approach to decide.  Updated - The New Law is simply a rule requiring brokers to track basis. Your situation doesn't change at all. When you sell the shares, you need to identify which shares you want to sell. For older shares, the tracking is your responsibility, that's all." I don't believe in letting the tax tail wag the investing dog. You have a stock you no longer wish to hold for whatever reason? Sell it. But to sell a loser, hoping it doesn't rise by the time you wish to re-buy it in 30 days is folly.  This effort may gain you $50 if done right. No, it's not worth it either way. In a comment on this answer you asked  It's not clear to me why the ability to defer the gains would matter (since you never materially benefit until you actually sell) but the estate step up in basis is a great point! Could you describe a hypothetical exploitive scenario (utilizing a wash sale) in a little more detail?  This sounds like you still have the same question as originally, so I'll take a stab at answering with an example.   I sell some security for a $10,000 profit.  I then sell another security at a $10,000 loss and immediately rebuy.  So pay no taxes (without the rule).  Assuming a 15% rate, that's $1500 in savings which I realize immediately.  Next year, I sell that same security for a $20,000 profit over the $10,000 loss basis (so a $10,000 profit over my original purchase).  I sell and buy another security to pay no taxes.  In fact, I pay no taxes like this for fifty years as I live off my investments (and a pension or social security that uses up my tax deductions).  Then I die.  All my securities step up in basis to their current market value.  So I completely evade taxes on $500,000 in profits.  That's $75,000 in tax savings to make my heirs richer.  And they're already getting at least $500,000 worth of securities.   Especially consider the case where I sell a privately held security to a private buyer who then sells me back the same shares at the same price.   Don't think that $10,000 is enough?  Remember that you also get the original value.  But this also scales.  It could be $100,000 in gains as well, for $750,000 in tax savings over the fifty years.  That's at least $5 million of securities.   The effective result of this would be to make a 0% tax on capital gains for many rich people.   Worse, a poorer person can't do the same thing.  You need to have many investments to take advantage of this.  If a relatively poor person with two $500 investments tried this, that person would lose all the benefit in trading fees.  And of course such a person would run out of investments quickly.   Really poor people have $0 in investments, so this is totally impractical. "You've laid out a strategy for deciding that the top of the market has passed and then realizing some gains before the market drops too far.  Regardless of whether this strategy is good at accomplishing its goal, it cannot by itself maximize your long-term profits unless you have a similar strategy for deciding that the bottom of the market has passed.  Even if you sell at the perfect time at the top of the market, you can still lose lots of money by buying at the wrong time at the bottom. People have been trying to time the market like this for centuries, and on average it doesn't work out all that much better than just plopping some money into the market each week and letting it sit there for 40 years. So the real question is: what is your investment time horizon?  If you need your money a year from now, well then you shouldn't be in the stock market in the first place.  But if you have to have it in the market, then your plan sounds like a good one to protect yourself from losses. If you don't need your money until 20 years from now, though, then every time you get in and out of the market you're risking sacrificing all your previous ""smart"" gains with one mistimed trade.  Sure, just leaving your money in the market can be psychologically taxing (cf. 2008-2009), but I guarantee that (a) you'll eventually make it all back (cf. 2010-2014) and (b) you won't ""miss the top"" or ""miss the bottom"", since you're not doing any trading." "If you're asking this question, you probably aren't ready to be buying individual stock shares, and may not be ready to be investing in the market at all.  Short-term in the stock market is GAMBLING, pure and simple, and gambling against professionals at that. You can reduce your risk if you spend the amount of time and effort the pros do on it, but if you aren't ready to accept losses you shouldn't be playing and if you aren't willing to bet it all on a single throw of the dice you should diversify and accept lower potential gain in exchange for lower risk. (Standard advice: Index funds.)  The way an investor, as opposed to a gambler, deals with a stock price dropping -- or surging upward, or not doing anything! -- is to say ""That's interesting. Given where it is NOW, do I expect it to go up or down from here, and do I think I have someplace to put the money that will do better?"" If you believe the stock will gain value from here, holding it may make more sense than taking your losses.  Specific example: the mortgage-crisis market crash of a few years ago. People who sold because stock prices were dropping and they were scared -- or whose finances forced them to sell during the down period -- were hurt badly. Those of us who were invested for the long term and could afford to leave the money in the market -- or who were brave/contrarian enough to see it as an opportunity to buy at a better price -- came out relatively unscathed; all I have ""lost"" was two years of growth. So: You made your bet. Now you have to decide: Do you really want to ""buy high, sell low"" and take the loss as a learning experience, or do you want to wait and see whether you can sell not-so-low. If you don't know enough about the company to make a fairly rational decision on that front, you probably shouldn't have bought its stock." For ESPP, the discount that you get is taxed as ordinary income. Capital gains is taxed at the appropriate rate, which is different based on how long you hold it. So, yes, if the stock is going up, For one, the startup doesn't exist yet, so until March I will get nothing on hand, though I have enough reserves to bridge that time. I would not take this deal unless the start-up exists in some form.  If it's just not yet profitable, then there's a risk/reward to consider.  If it doesn't exist at all, then it cannot make a legal obligation to you and it's not worth taking the deal yet.  If everything else is an acceptable risk to you, then you should be asking the other party to create the company and formalize the agreement with you. As regards reserves, if you're really getting paid in shares instead of cash, then you may need them later.  Shares in a start-up likely are not easy to sell (if you're allowed to sell them at all), so it may be a while before a paycheck given what you've described. For a second, who pays the tax? This is my first non-university job so I don't exactly know, but usually the employer has to/does pay my taxes and some other stuff from my brutto-income (that's what I understood). If brutto=netto, where is the tax? This I cannot answer for Germany.  In the U.S. it would depend in part on how the company is organized.  It's likely that some or all of the tax will be deferred until you monetize your shares, but you should get some professional advice on that before you move forward.  As an example, it's likely that you'd get taxed (in part or in whole) on what we'd call capital gains (maybe Abgeltungsteuer in German?) that would only be assessed when you sell the shares. For third, shares are a risk. If I or any other in the startup screw really, my pay might be a lot less than expected. Of course, if it works out I'm rich(er). This is the inherent risk of a start-up, so there's no getting around the fact that there's a chance that the business may fail and your shares become worthless.  Up to you if you think the risk is acceptable.  Where you can mitigate risk is in ensuring that there's a well-written and enforceable set of documents that define what rights go with the shares, who controls the company, how profits will be distributed, etc.  Don't do this by spoken agreement only.  Get it all written down, and then get it checked by a lawyer representing your interests. If your criteria has changed but some of your existing holdings don't meet your new criteria you should eventually liquidate them, because they are not part of your new strategy. However, you don't want to just liquidate them right now if they are currently performing quite well (share price currently uptrending).  One way you could handle this is to place a trailing stop loss on the stocks that don't meet your current criteria and let the market take you out when the stocks have stopped up trending. "Because I feel the answers given do not wholely represent the answer you are expecting, I'd like to re-iterate but include more information. When you own stock in a company, you OWN some of that company. When that company makes profit, you usually receive a dividend of those profits. If you owned 1% of the company stock, you (should) recieve 1% of the profits. If your company is doing well, someone might ask to buy your stock. The price of that stock is (supposed) to be worth a value representative of the expected yield or how much of a dividend you'd be getting.  The ""worth"" of that, is what you're betting on when you buy the stock, if you buy $100 worth of coca cola stock and they paid $10 as dividend, you'd be pretty happy with a 10% growth in your wealth. Especially if the banks are only playing 3%. So maybe some other guy sees your 10% increase and thinks, heck.. 10% is better than 3%, if I buy your stocks, even as much as 6% more than they are worth ($106) I'm still going to be better off by that extra 1% than I would be if I left it in the bank.. so he offers you $106.. and you think.. awesome.. I can sell my $100 of cola shares now, make a $6 profit and buy $100 worth of some other share I think will pay a good dividend. Then cola publicises their profits, and they only made 2% profit, that guy that bought your shares for $106, only got a dividend of $2 (since their 'worth' is still $100, and effectively he lost $4 as a result. He bet on a better than 10% profit, and lost out when it didn't hit that. Now, (IMHO) while the stock market was supposed to be about buying shares, and getting dividends, people (brokers) discovered that you could make far more money buying and selling shares for 'perceived value' rather than waiting for dividends to show actual value, especially if you were not the one doing the buying and selling (and risk), but instead making a 0.4% cut off the difference between each purchase (broker fees). So, TL;DR,  Many people have lost money in the market to those who made money from them. But only the traders and gamblers." You should constantly look at your investment portfolio and sell based on future outlook. Don't get emotional. Selling a portfolio of stocks at once without a real reason is foolish.  If you have a stock that's up, and circumstances make you think it's going to go up further, hold it. If prospects are not so good, sell it. Also, you don't have to buy or sell everything at once. If you've made money on a stock and want to realize those gains, sell blocks as it goes up. Stay diversified, monitor your portfolio every week and keep a reserve of cash to use when opportunity strikes. If you have more stocks or funds than you can keep current on every week, you should consolidate your positions over time. I'm not sure where people keep getting this idea, but I see it come up a lot. Anyway, you pay capital gains taxes when you sell an investment that has appreciated. It makes no difference when/if you reinvest the money or what you invest it in. If you are afraid of the tax burden you can minimize it by: 1) Selling a stock that you have held longer than a year to get the lower long-term rate. 2) Sell a stock that hasn't appreciated that much and therefore doesn't have a lot of gains to tax. 3) Sell a stock that's below purchase price (i.e. at a loss) to offset any short term gains. Don't sell. Ever.  Well almost. A number of studies have shown that buying equal amounts of shares randomly will beat the market long term, and certainly won't do badly.  Starting from this premise then perhaps you can add a tiny bit extra with your skill... maybe, but who knows, you might suck.  Point is when buying you have the wind behind you - a monkey would make money. Selling is a different matter. You have the cost of trading out and back in to something else, only to have changed from one monkey portfolio to the other. If you have skill that covers this cost then yes you should do this - but how confident are you? A few studies have been done on anonymised retail broker accounts and they show the same story.  Retail investors on average lose money on their switches. Even if you believe you have a real edge on the market,  you're strategy still should not just say sell when it drops out of your criteria.  Your criteria are positive indicators. Lack of positive is not a negative indicator.  Sell when you would happily go short the stock.   That is you are really confident it is going down. Otherwise leave it. Thanks for this, great in depth answer. I had previously calculated a WACC and have used it for my discount rate.   As part of your last point on revenue vs. cash, I've set a accounts receivable period of 30 days, and then applied a factor of 30/365 * revenue to understand what portion of my revenue is not cash in hand. Does that make sense? "In my view, it's better to sell when there's a reason to sell, rather than to cap your gains at 8%. I'm assuming you have no such criteria on the other side - i.e. hold your losses down to 8%. That's because what matters is how much you make overall in your portfolio, not how much you make per trade. Example: if you own three stocks, equal amounts - and two go up 20% but one falls 20%. If you sell your gains at 8%, and hold the loser, you have net LOST money. So when do you actually sell? You might say a ""fall of 10%"" from the last high is good enough to sell. This is called a ""trailing"" stop, which means if a stock goes from 100 to 120, I'll still hold and sell if it retraces to 108. Needless to say if it had gone from 100 to 90, I would still be out. The idea is to ride the trend for as long as you can, because trends are strong. And keep your trailing stops wide enough for it to absorb natural jiggles, because you may get stopped out of a stock that falls 4% but eventually goes up 200%. Or sell under other conditions: if the earnings show a distinct drop, or the sector falls out of favor.  Whenever you decide to sell, also consider what it would take for you to buy the stock back - increased earnings, strong prices, a product release, whatever. Because getting out might seem like a good thing, but it's just as important to not think of it as saying a stock is crappy - it might just be that you had enough of one ride. That doesn't mean you can't come back for another one."