How to Number Auction Lots for a Coin Sale

To number auction lots for a coin sale, give the lots consecutive numbers in the order bidders should see them, start each sale or session at a number you choose, and never change a number after the catalog is published. Leave room for late additions by using a letter after an existing number, such as 12A, instead of renumbering. If you sell by category, a short prefix per category, such as MD-001 for Morgan dollars, keeps each group in its own sequence.

Lot numbers look like a small detail. In a sale of 1,800 lots, they are the key that ties the catalog, the bids, the platform's results report, and your invoices together. A bad numbering scheme shows up as a reconciliation problem after the sale.

What a lot number has to do

A lot number must:

1. Be unique within the sale. One number, one lot.
2. Sort in catalog order. Bidders browse by number.
3. Stay the same once published. Bidders, watch lists, the platform, and your results file all refer to it.
4. Fit the platform's rules. Some platforms want digits only, or limit the length.

Everything else is your choice.

Common lot numbering schemes

Plain sequential numbers

1, 2, 3, up to the last lot. Simple, and every platform accepts it. It works well for one sale with one session.

A starting number per sale or session

Start the November sale at 1001 and the December sale at 2001. Or start session one at 1 and session two at 1001. The number alone tells you which sale or session a lot belongs to, which helps when you pull coins from the vault.

A prefix per category

Category	Prefix and first number	Lots
Morgan dollars	MD-001	MD-001 to MD-412
Gold	G-0001	G-0001 to G-0187
Everything else	1	1 to 1,243

Each prefix counts on its own. Use zero padding (MD-001 instead of MD-1) so the numbers sort the same way as text and as numbers. Check that the platform accepts letters and a separator before you use this scheme.

Which scheme wins when several apply

If you use more than one scheme, decide which applies first. A sensible order is the most specific first: a rule for this one sale, then a rule for the coin's category, then a rule for the platform, then a default for all sales.

Adding lots after the catalog is published

Late consignments arrive. A coin comes back from grading. You want it in the sale, next to similar coins, but the catalog is already out.

Do not renumber. Insert the new lot with a letter after the lot it follows:

Lot	Coin
12	1889-CC Morgan dollar, NGC F-12
12A	1889-CC Morgan dollar, PCGS VG-10 (added late)
13	1890-CC Morgan dollar, PCGS VF-25

Lot 12A sorts between 12 and 13, and no other number changes. If you need two inserts, use 12A and 12B.

If the new coin does not need a specific place, give it the next number after the highest lot in the sale.

Lots that were never exported

Before a catalog is published or uploaded, lot numbers are still yours to change. If you added coins in a random order while building the sale, renumber the unpublished lots once, in the order you want bidders to see. After the first export, freeze them.

Withdrawn lots

When a coin sells somewhere else before the sale, or a consignor pulls it, withdraw the lot and keep its number. Mark it withdrawn on the platform. Never give that number to another coin; old watch lists and absentee bids still point at it.

Sessions in a live sale

A live sale of 1,500 lots often runs over two or three sessions. Number each session from its own round start, such as 1 to 650 for session one and 1001 to 1850 for session two. Bidders see the session from the number, your staff pull coins by session, and a late addition to session one never collides with session two.

Timed sales do not have sessions, but the same idea works for closing groups: lots 1 to 500 close on the first evening, lots 501 to 1000 on the next.

Lot numbers in the results report

After the sale, the platform's results report refers to each lot by its number and nothing else. If your numbers changed after the export, the report's lot 1458 is not your lot 1458, and the wrong coin gets marked sold. This is the main reason to freeze numbers: reconciliation depends on it. See how to reconcile auction results.

Keep the coin's SKU or inventory number in the lot description or a catalog field as a second key. If a number ever does go wrong, the SKU lets you find the coin.

Two people numbering at once

When several people build one large sale, two of them can pick the same next number at the same moment. Take numbers from one place, one batch at a time, and check the sale for duplicate numbers before every export.

Worked example: a 1,842-lot sale

A dealer builds a HiBid sale over three weeks:

1. Week one: 1,200 coins added. Numbers 1001 to 2200 from the HiBid rule.
2. The catalog goes out to HiBid. Numbers 1001 to 2200 are now fixed.
3. Week two: 600 more coins. They get 2201 to 2800.
4. Week three: 42 late coins. Thirty go at the end, 2801 to 2830. Twelve need to sit next to specific coins and take letters, such as 1458A.
5. Second export: only the new lots go out. Nothing already on HiBid changes number.

The results report after the sale refers to every lot by these numbers, and each one points at exactly one coin.

Common mistakes

• Renumbering after export. The platform keeps the old number; your records do not match.
• Reusing a withdrawn number. Results and bids attach to the wrong coin.
• Numbers without padding when prefixes are used. MD-10 sorts before MD-2 as text.
• Letters on a platform that does not accept them. The upload fails or the numbers change on import.
• Numbering in a spreadsheet next to the inventory. Two lists drift apart.

How CoinManagerPro numbers lots

In CoinManagerPro, lot number rules set the format: a prefix of up to 4 letters or digits, a separator, a start number, and zero padding. A rule can cover all sales, one platform, one category, or one sale; the sale rule applies first, then category, then platform, then the rule for all sales. Without a rule, a new lot gets the next number after the highest in the sale.

You select coins on the Coins page and choose Assign lot numbers. Coins not in the sale become lots. Once a lot is exported, its number does not change, and a coin added after the export can take a letter after a lot, such as 12A. Renumber lots not exported puts the unexported lots in order by your rules. Two people can assign numbers in the same sale at the same time without a duplicate. The same rules number the lots of your Flow auctions. The auction readiness and lot numbers help article has the steps.