Most poker rooms will offer you a welcome bonus if you register with them and deposit money in to your account. This id their way of motivating you to sign up and make a deposit. The size and exact design of these bonuses vary, but they are often based around the amount you deposit, i.e. the bonus is often 100% or 200% percent of your initial deposit. This means that if the welcome bonus is 100% and you deposit USD 200 you get a USD 200 bonus. There is usually a ceiling for how big the bonus can get, and regardless of how much money you deposit that is the biggest bonus you can be awarded.
A poker bonus might as an example be 200% up to USD 500. This usually means that the biggest possible bonus is USD 1,000 and that you get that by depositing USD 500. However, the same expression can sometimes mean that the highest possible bonus is USD 500 which you in that case would receive if you deposited USD 250. The lack of a universal standard for how the bonus is formulated is why it is very important to read the fine print before choosing to get register at a poker room to get the welcome bonus. It should however be mentioned that the bonus should never be the primary reason why you choose a specific poker room. Instead, the games offered and the opponents that play there should be your main considerations if you want to be a winning player in the long run. Deposit and withdraw options should also be consider.
The size of the bonus is not the only factor to look at when evaluating poker bonuses. This is due to the fact that bonuses are only seldom deposited in your account directly and is almost never without strings. Most commonly, the poker bonus is released to you in chunks once you earned it, and you usually earn it by playing in raked hands and collect enough player points. This basically means that the bonus to a large part is money you paid into the rake that they give back to you as a new player.
It is important to check how much you need to play to get your bonus released. Some poker rooms are a lot more generous in this regard than others who require that you play a lot more before you get your bonus money. You should also see in how big chunks the bonus is released. It is off course much easier to get your hands on a bonus that is released in increments of USD 5 than one where you have to release USD 50 or even more before anything is placed in your account.
It is also important to check how much time you have to release the bonus since the part that has not been released in a certain time frame usually is forfeited. It is common to have 30, 60 or 90 days to earn the bonus before it is forfeited. Having 90 days to earn the needed points will of course make it a lot easier to actually get the bonus than what would be the case if you only got 30 days. This is especially true if you are a recreational player that only plays now and then.
The welcome bonus is likely the biggest bonus you will ever get from a poker room. Sometimes they may offer reload or special deposit bonuses that are equally generous, but later bonuses are normally smaller than the welcome bonus. This does not mean that you should look only at the welcome bonus and ignore the bonuses a poker room has for existing players. These might be smaller but can still be worth more money in the long run if you stay with specific poker room for some time. Check and see if the poker rooms your are evaluating have any regular bonuses for current members or if they have a history of a lot of special offers and perks for such members. If they do it is clearly something speaking in their favor, but as mention earlier the bonuses offered should never be the main reason for choosing a poker room.