Double Stacks Slot Review
Free demo, RTP, volatility and max win
7.1Value score · Good · how it works
Double Stacks review: NetEnt's 2018 fruit-and-diamond slot on 5x3 reels with 10 lines, doubled full-reel stacks and a 96.1% RTP, rated High.
- 44%of slots have a lower headline RTP
Play Double Stacks free: demo, no sign-up
Free play money from NetEnt's official demo. 18+. No deposit and no account; a demo does not predict real results.
Basic information
| Software | NetEnt |
|---|---|
| Release year | 2018 |
| RTP | 96.1% |
| Volatility | High |
| Max win | x1,700 |
| Hit frequency | 16% of spins |
| Features | Free spins |
| Game type | Slot |
| Data verified | 2026-09-28 |
Source: NetEnt game page; RTP database by toolsgambling.com (CC BY 4.0); image: NetEnt promotional image from the official game page. How we collect data · Report a mistake
Double Stacks review
NetEnt's 2018 slot keeps to a classic layout: five reels, three rows, ten lines, and fruit and diamond symbols. Its one trick is in the name. When a whole reel fills with the same high-paying symbol, each of those symbols counts twice towards the win. A free spins bonus adds stacked wilds to the reels. There is little else in the rules, so the review is brief, and the numbers are those of a High volatility slot with a 1,700x ceiling.
How the doubling works
The feature applies to the four highest-paying symbols. If a reel is completely filled with one of them, the symbols on that reel double and count as two each when the win is calculated. On a three-row reel that turns three symbols into six for counting purposes.
The same rule explains the largest line win the studio mentions: up to a 10-symbol win on any bet line. With five reels, that is the result of every reel being filled with the matching symbol and each one counting twice. Because the rule needs a full reel of one of the top four symbols, it can apply only on spins where a reel fills completely, so the doubling is an occasional boost, not a steady one.
Free spins with stacked Wilds
Three or more Scatter symbols in the main game start the free spins. During the round, stacked Wilds are added to the reels. The studio also says stacked Wilds can double in the free spins, which opens the door to larger wins across the reels. The number of free spins awarded is not stated in the material we hold.
RTP, hit rate and top prize
One RTP is recorded: 96.1%, a house edge of 3.9%. That is about $39 lost per $1,000 wagered over a long run. In short sessions, 100 spins at $0.20 cost $0.78 on average, 100 spins at $1 cost $3.90, and 100 spins at $5, or $500 wagered, cost $19.50.
Volatility is High and the hit frequency is 16%, so about one spin in six produces a win. The max win is 1,700x the bet, which equals $340 at a $0.20 bet, $1,700 at $1 and $8,500 at $5.
Similar High-volatility slots
Disco Danny lists 96.04% and the same 1,700x. RAGE (2024) shows 96.08% and 1,800x, Dark King: Forbidden Riches 96.06% and 1,600x, and Jack Hammer 3: Diamond Affair 96.08% and 1,300x. Elk Hunter has the same 96.1% as Double Stacks with a 2,000x ceiling, while Golden Egg Invaders reaches 96.13% and 2,200x. On these figures Double Stacks sits in the middle of its group.
Pros
- Full-reel stacks of the top four symbols count double
- A published 16% hit frequency
- Stacked Wilds in the free spins, which can also double
- A simple 5x3 layout with 10 lines
Cons
- A 1,700x max win is modest for a High-volatility slot
- The free spin count and Wild details are not given in our sources
Verdict
Double Stacks is a classic fruit-and-diamond slot with one distinctive rule, doubled full-reel stacks, and a free spins round with stacked Wilds. The 96.1% RTP is a 3.9% house edge, volatility is High and the top prize is 1,700x. As paid entertainment it costs about $39 per $1,000 wagered on average, which suits players who like simple rules and can accept a win on only one spin in six.
Sources: NetEnt official game page; RTP, volatility and max win from the open Slot RTP Database.
Slots like Double Stacks
Double Stacks RTP
The data lists one RTP for Double Stacks. Versions are not tracked for NetEnt games, so other versions may exist; check the game's info screen.
- 96.1% $39 lost per $1,000
Cost of 100 spins
| Bet | Wagered | Average cost at 96.1% |
|---|---|---|
| $0.20 | $20 | $0.78 |
| $1 | $100 | $3.90 |
| $5 | $500 | $19.50 |
Averages computed from the published RTP; real sessions vary widely around them. RTP calculator
Double Stacks max win, volatility & stats
- Value score
- 7.1 / 10
- Lost per $1,000 (average)
- $39
- Max win at $1 bet
- $1,700
- Wins on average
- 1 in 6.3 spins
Percentiles compare this game with the 3,708 games in the catalogue. Max win: 1,700×.
