To answer "What is a sticky bonus?", start with how the offer is built. A welcome offer is rarely one bonus. It is usually a package spread across several deposits, each with its own match percentage, ceiling and conditions, and sometimes with free spins attached. The headline adds the parts together, which makes the whole look larger than any one step. Taking the package apart shows what each deposit actually earns and what it asks in exchange.
Every offer names a qualifying deposit, a minimum below which no bonus is paid. Some also require a code at the cashier or a tick in an opt in box before the payment, and a deposit made without it rarely earns the bonus afterwards. Certain payment methods, often electronic wallets and prepaid cards, are excluded from welcome offers in the terms. Checking the method and the code before paying avoids a deposit that earns nothing at all.
Reload offers return after the welcome package, often weekly, with smaller matches and the same kind of wagering. Whether any bonus is sticky or cashable matters as much as its size. A sticky bonus can be played with but is removed at withdrawal, so only the winnings above it can be cashed. A cashable bonus becomes part of the balance once the requirement is met. The terms name the type, sometimes under another label.
A match bonus adds a percentage of the deposit, up to a ceiling. A hundred percent match up to a stated maximum doubles a deposit that stays under the ceiling, and adds nothing to the part above it. Higher percentages usually come with lower ceilings or heavier wagering. Comparing offers by the bonus a planned deposit would actually receive, instead of the largest figure in the banner, keeps the comparison honest and often reverses the order of two competing offers.
A sticky bonus is removed at withdrawal, leaving only the winnings above it, while a cashable bonus joins the balance once wagering is met.
A match bonus adds a percentage of the deposit up to a stated maximum, so a full match doubles a deposit under the ceiling and adds nothing above it.
Bonuses that return after the welcome package, often weekly, with smaller matches and the same kind of wagering attached.
Each tier unlocks only after the previous one is claimed, often within a set number of days from registration, and later tiers usually match smaller percentages.
Some offers only apply when a box is ticked before payment, and a deposit made without opting in usually earns nothing afterwards.
Some offers need a code at the cashier or at sign up before paying, and a deposit made without it rarely earns the bonus afterwards.