A welcome bonus is a casino's offer to new players, usually a deposit match (for example 100% up to €500) sometimes combined with free spins. What matters most is rarely the bonus amount but the wagering requirement: a 100% bonus at 35x is usually better than 200% at 60x. Also check the minimum deposit, the time limit and which games contribute to wagering.
Below we compare the current welcome bonuses. Choose licensed operators, and if you have activated self-exclusion, respect it — it applies across all licensed casinos.