Set 40912
Sea Serpent
On shelves nowRetail price—Not on file
Worth now$39.76Based on 741 recent sealed sales
Asking now$45.00Typical price on 47 eBay listings
vs retail—Needs both prices
No retail price on file
Worth $40 today, but without a retail price there's nothing to judge that against.
How much is LEGO 40912 Sea Serpent worth?
LEGO 40912 Sea Serpent is worth about $39.76 sealed right now, based on 741 recent sealed sales. It came out in 2026 with 241 pieces. It's still sold in shops. Over the last 84 days its typical asking price has fallen 17%, from $54.47 to $45.00. We last checked it 6 days ago.
Price history
Value history
Oct 19$4547 listings
- Lowest
- $45
- Highest
- $55
- Change
- -17%
- Asking vs retail
- —
27 observations · median asking · rechecked 8× daily
Should you buy it?
47 listings behind this — one of the better-evidenced values on the site.
If you bought it to resell
Sells sealed for$40
Marketplace fees · 15.25%−$6
Payment processing · 2.9% + $0.30−$2
Shipping · est. from 241 pieces−$9
Reaches you$23
Pay no more than$18
For a 30% return at your costs. Change them and every figure on the site follows.
How long has it been on shelves?
Still early — released 2026, and sets like this usually run about 3 years. No hurry.
LEGO never announces retirement dates. This is only how long the set has been available against how long sets of its size usually run — not a prediction, and not inside information.
What it actually sold for
Sealed
$40
741 sold in six months · $28–$56Used
$28
1 sold in six monthsSellers are asking 13% more than buyers actually paid. The $45 figure above is a ceiling; this is the floor to negotiate toward.
Completed BrickLink transactions over the last six months. Real sales, not asking prices.
Set details
- Set number
- 40912
- Theme
- LEGO Ideas and CUUSOO
- Released
- 2026
- Status
- On shelves now
- Pieces
- 241
- Minifigures
- —
- Retail price
- —
- Value per piece
- $0.187
- Price confidence
- high · 47 listings
- Last checked
- 6 days ago
Where these numbers come from
eBay47 live listingsThe asking price here — the median of what sellers want right now, $45. Last checked Oct 19.See the listings →BrickLink741 completed salesWhat it actually sold for — $40 across six months of real transactions. Last checked Oct 24.Open the price guide →Catalogue241 piecesPiece counts, minifigures, release year and retail price come from Rebrickable and Brickset.See the catalogue entry →
eBay links are affiliate links — if you buy after clicking, we earn a small commission at no cost to you, and that is what pays for the site. BrickLink has no such programme, so those are plain links. Neither changes what we show or what we say about it.
How to read this. The value is the median of live sealed listings, after removing instructions, empty boxes, used sets, multi-set lots and implausible outliers. Real sale prices usually land below asking, so the buy-below figure is deliberately the conservative end of the range.
More LEGO Ideas and CUUSOO sets from around 2026
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