Storage means renting a tank to hold crude oil when you don't want to sell it immediately.
You store oil when: (1) you can't find a buyer today, (2) the forward curve is in contango so future prices are higher, or (3) you are waiting for a better market. Every day in storage costs money.
Storage cost components โ where the money goes
| Cost component | Typical rate | On 1M bbls/month | Why it exists |
| Tank rental fee | $0.20โ$0.40/bbl/month | $200kโ$400k/month | Tank operator's margin for providing facility |
| Insurance | $0.02โ$0.05/bbl/month | $20kโ$50k/month | Coverage for fire, spill, contamination risk |
| Heating (heavy crude) | $0.03โ$0.08/bbl/month | $30kโ$80k/month | Heavy crude solidifies โ must keep heated |
| Loss allowance | 0.05โ0.15% per month | ~$40k/month | Evaporation, metering loss, tank bottom loss |
| Capital charge | $18,230/day (8% rate) | $546k/month | Cost of company money tied up in inventory |
| Total storage cost | ~$0.80โ$1.10/bbl/month | ~$836kโ$1.1M/month | |
Tank fill level โ visual
Empty tank
5% full
Losing money on fixed costs
Half full
50% full
Moderate cost efficiency
Full tank
95% full
Best cost per barrel
Overfill risk
100%
Safety risk โ must sell fast
The contango storage trade: buy spot, store, sell forward.
When the market is in contango (future prices higher than spot), you can lock in a profit by buying cheap oil today, storing it, and simultaneously selling it forward at the higher future price. If the contango is wide enough to cover storage costs โ it's a guaranteed profit.
The full calculation โ does the contango cover costs?
Spot price today$80.00 / bbl
3-month forward price$83.50 / bbl
=Contango gain+$3.50 / bbl over 3 months
Tank rental (3 months)โ$0.90 / bbl
Insurance + lossesโ$0.20 / bbl
Capital charge (90 days)โ$1.64 / bbl($80 ร 8% ร 90/365)
Financing costโ$0.27 / bbl
Net storage profit = $3.50 โ $3.01 = +$0.49 / bbl
On 1,000,000 barrels: +$490,000 locked-in profit for 3 months work
This is the famous "cash and carry" trade. When contango is steep (like during COVID-2020 when WTI went negative), traders filled every available tank and tanker with crude and locked in enormous profits. The trade is fully hedged โ you buy physical AND simultaneously sell the forward swap โ so flat price risk is zero. Pure logistics arbitrage.
When NOT to store: if the market is in backwardation (spot > forward), every day you store is a loss. You paid $83 for spot oil but can only sell forward at $81. Storage costs are on top. This is why in a backwardated market, physical traders move barrels as fast as possible โ storing is suicide.
Storage economics simulator โ does your contango trade make money?
Contango gain$83.50 โ $80.00 = +$3.50/bbl
โTank rental$0.30 ร 3 months = $0.90/bbl
โCapital charge$80.00 ร 8% ร 90/365 = $1.58/bbl
โInsurance + loss$0.07/bbl ร 3 months = $0.21/bbl
Net storage P&L = +$3.50 โ $2.69 = +$0.81/bbl
On 1,000,000 bbls: +$810,000 total
Total storage cost
$2.69/bbl