Cost Basis Tracker

What Counts as Cost Basis?

Cost basis is the total amount you invested in acquiring a collectible, including all costs directly related to the purchase. Under Treas. Reg. §1.263(a)-1(e), the cost of acquired property includes the invoice price, plus all costs incident to the purchase — not just the hammer price or sticker price.

For collectibles, cost basis generally includes:

• Purchase price — the amount paid to the seller or auction house for the item itself
• Buyer’s premium — the percentage surcharge added by auction houses (typically 15–28% at major houses like Heritage, Sotheby’s, and Christie’s)
• Sales tax — state and local sales tax paid at the point of purchase
• Shipping and handling — delivery costs paid to receive the item
• Insurance — transit insurance purchased to protect the item during shipping
• Grading and authentication fees — fees paid to PSA, BGS, CGC, NGC, PCGS, or other grading services to authenticate and encapsulate the item

All of these costs are added together to form the adjusted cost basis, which is the number subtracted from the sale proceeds when calculating gain or loss. A higher basis means a lower taxable gain.

For a complete walkthrough with examples, see our cost basis guide for collectors.

Why Tracking Basis Matters

Under IRC §1001, gain from the sale of property is the excess of the amount realized over the adjusted basis. The “amount realized” is the sale price minus selling expenses. The “adjusted basis” is the original cost plus improvements and acquisition costs.

The burden of proof for cost basis rests with the taxpayer. If the IRS questions a sale and the taxpayer cannot substantiate the original cost, the IRS may treat the basis as zero — meaning the entire sale price becomes taxable gain. For collectibles taxed at the 28% maximum rate under IRC §1(h)(4), that can translate to a significant and entirely avoidable tax bill.

Consider a collector who buys a PSA 10 1986 Fleer Michael Jordan rookie card for $25,000, pays a 20% buyer’s premium ($5,000), $150 in shipping, and $75 in sales tax. Their true cost basis is $30,225. If they later sell for $40,000, their actual gain is $9,775 — not $40,000. Without records, the IRS could assess tax on the full $40,000.

Maintaining organized records — whether through this tracker, a spreadsheet, or receipts in a shoebox — provides the documentation needed to substantiate basis in the event of an IRS inquiry. The Export CSV feature in this tool creates a backup you can save to your files for future reference.

Common Basis Items Collectors Miss

Many collectors track the purchase price but overlook other legitimate components of cost basis. These items add up, and failing to include them results in overstating gain.

Grading and Authentication Fees

Fees paid to PSA, BGS (Beckett Grading Services), CGC (comics), NGC and PCGS (coins) are part of cost basis. A PSA submission at the $150 tier, plus return shipping, is a cost directly related to the item. If grading increases the item’s marketability and eventual sale price, the fee is a capital expenditure under general tax principles and is added to basis.

Buyer’s Premium

Auction houses charge buyers a premium on top of the hammer price. Heritage Auctions charges 20% for most lots. Sotheby’s and Christie’s have tiered premiums that can exceed 25%. This premium is part of the acquisition cost and belongs in basis. On a $10,000 lot with a 20% premium, the buyer actually pays $12,000 — and $12,000 is the starting point for basis, not $10,000.

Shipping and Insurance

Shipping paid to receive a purchased item — whether from an eBay seller, an auction house, or a dealer — is part of basis. If you paid $35 for Priority Mail and $15 for declared-value insurance on a coin purchase, that $50 belongs in your basis calculation. Collectors who buy from overseas may also have customs duties, which are similarly includable.

Sales Tax Paid at Purchase

State and local sales tax paid when acquiring a collectible is part of cost basis. If you buy a $500 comic at a shop in Texas and pay 8.25% sales tax ($41.25), your basis is $541.25. This applies to in-person purchases, online purchases where sales tax was collected, and auction purchases where applicable.

Sources

• Treas. Reg. §1.263(a)-1(e) — Amounts paid to acquire or produce tangible property
• IRC §1001 — Determination of amount of and recognition of gain or loss
• IRC §1(h)(4) — Maximum 28% rate on collectible gains
• IRC §1222 — Other terms relating to capital gains and losses (holding period definitions)