Potion decanting: turning cheap doses into 4-dose profit
How decanting works on the GE: comparing price per dose, combining with Bob Barter, the tax on the 4-dose sale, and the best potions to decant today.
Offerbook · Published · 4 min read
Potions come in 1, 2, 3 and 4-dose sizes, and the GE prices each size separately. Players mostly want 4-dose potions, so smaller doses often sell for less per dose. Decanting means buying the cheap doses, combining them into 4-dose potions, and selling those.
How to decant
Bob Barter, who stands next to the Grand Exchange, decants potions for free. Hand him any mix of doses of the same potion and he gives you back as many 4-dose potions as the doses make. You can also combine doses by hand, one use at a time, but Bob is far quicker for a full inventory.
The sum
Compare prices per dose. A 3-dose potion at 7,200 gp costs 2,400 gp a dose. Four doses of that cost 9,600 gp. If the 4-dose sells for 10,000 gp, the 2% tax takes 200 gp of it.
- 4-dose sells for
- 10,000 gp
- GE tax (2%)
- − 200 gp
- 4 doses bought at 2,400 gp each
- − 9,600 gp
- Profit per 4-dose potion
- 200 gp
Doses only combine evenly in fours. Three 3-dose potions are 9 doses, which makes two 4-dose potions and leaves 1 dose over. Four 3-dose potions make exactly three 4-dose potions, so buy in multiples that come out even.
Best decants right now
| Potion (buy dose) | Cost / dose | Profit per 4 |
|---|---|---|
| Divine super defence potion (2) | 825 gp | 2,127 gp |
| Anti-venom (3) | 2,233 gp | 1,847 gp |
| Divine super attack potion (1) | 542 gp | 1,800 gp |
| Haemostatic dressing (2) | 950 gp | 1,644 gp |
| Super antifire potion (1) | 5,129 gp | 1,479 gp |
Profit per 4 is the 4-dose sale after tax, minus four doses bought at the cheapest size.
Things to watch
- Volume on both sides. The cheap dose has to trade often enough for you to buy it, and the 4-dose often enough for you to sell.
- Buy limits. Each dose size has its own limit, so you can sometimes buy more doses by mixing sizes.
- The gap is small. Decanting margins are often a few hundred gp per potion, so it pays in volume, not per potion.
The decanting calculator shows every potion family with its best source dose, and the decanting glossary entry has a live example. Other ways the GE pays, like item sets and high alching, are on the Strategies page.
Offerbook is gp only and has nothing to do with real-world trading. Prices move, so nothing here is a promise of profit. Every trade is one you make yourself in game.