- Wide-Area Progressive (WAP)
- A jackpot pool linked across multiple machines at multiple casino properties. Every qualifying bet at every linked machine feeds the same meter. The prize grows faster than a standalone jackpot — and is harder to win. MGM Grand Millions is a WAP title. Read the full breakdown in How Wide-Area Progressive Slots Actually Work.
- Standalone Progressive
- A jackpot fed only by a single machine. Smaller prize, better hit odds. See how the two formats compare in our WAP vs. standalone progressive guide.
- Progressive Meter
- The live running total displayed on the machine or game screen. It ticks up with every qualifying bet. When someone hits the jackpot, it resets to the seed amount. How that meter grows — and what triggers a hit — is covered on the jackpot mechanics page.
- Seed Amount
- The minimum value a progressive jackpot resets to immediately after being won. The meter starts climbing again from that floor the moment the next qualifying bet is placed.
- RTP (Return to Player)
- The theoretical percentage of total wagered money a slot returns over millions of spins. A 90% RTP means the house keeps 10% on average. WAP slots generally run 85%–92% because a slice of every bet feeds the jackpot pool instead of the base-game pay table.
- Volatility / Variance
- How often and how much a slot pays. High volatility means frequent small losses, rare large wins. MGM Grand Millions sits at the top of that scale. The full reasoning is explained in Why MGM Grand Millions Is Classified as Very High Volatility.
- Max Bet
- The highest credit amount allowed per spin. WAP jackpots typically require a qualifying or max bet to be eligible for the top prize. Playing below that threshold may lock you out of the progressive entirely.
- Playthrough / Wagering Requirement
- The number of times you must bet bonus funds before withdrawing them as cash. BetMGM Casino has historically set this at 15×–30× the bonus amount. Progressive jackpot slots often contribute at a reduced rate — or nothing at all. Details at BetMGM Bonus Wagering: Why MGM Grand Millions May Not Count.
- W-2G
- The IRS tax form a casino issues when you win $1,200 or more on a single slot spin. Wins of $5,000 or more net of the wager trigger automatic 24% federal withholding at payout. The full picture is on the W-2G form explained page.
- KYC (Know Your Customer)
- Identity verification an online casino runs before processing large withdrawals — typically a government-issued ID and proof of address. Large progressive jackpot wins almost always trigger an additional KYC review, which can extend payout timelines beyond the standard window. See how fast BetMGM pays out a jackpot win.
- Play+ Card
- A regulated prepaid card BetMGM offers for deposits and withdrawals. Withdrawals to Play+ typically take 1–3 business days. It is one of several funding options covered on the deposit methods page.
- GeoComply
- Third-party geolocation software licensed online casinos use to confirm your device is physically inside a legal state border. BetMGM uses it to comply with the licensing rules set by regulators such as the NJ Division of Gaming Enforcement and the Michigan Gaming Control Board. A VPN will trigger a block and can result in account suspension.
Those 12 terms cover the language you will encounter reading bonus T&Cs, regulator filings, and game reviews for the MGM Grand Millions jackpot. Bookmark this page and refer back whenever a phrase stops you cold.
State income tax rates on jackpot wins — New Jersey tops out at 10.75%, Michigan sits at 4.25%, Pennsylvania at 3.07% — are broken out further on the state income tax on slot winnings page. And if you want to compare the land-based and online experiences side by side, see the mgm grand millions slot casino floor vs. online version comparison.
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