USDC's 13 Networks: $6 Small-Swap Tax, 228× Ceiling Gap

One ticker, thirteen order books. USDC looks like a single asset in a wallet, but the catalogue behind veilswap.io lists thirteen USDC assets — Ethereum, Polygon, Solana, BSC, Avalanche C-Chain, Arbitrum, Base, Sui, Aptos, Monad, Sei, ARC and Asset Hub — inside a directory of 448 assets on 65 networks, 51 stablecoins and six assets that require an extra ID. Between 06:04:33 and 06:05:22 UTC on 2026-11-09 I sent the same three amounts, 100, 1,000 and 5,000 USDC, to XMR on every network the quote API would accept. The result is not one winner but three separate problems: a small-amount haircut, one network that never joins the main group, and ceilings that differ by 228 times. (SOL to XMR guide)

Same ticker, different rails. The thirteen entries are separate asset ids, not aliases: each has its own network, its own deposit address format and its own quote. One absence is worth stating up front: there is no USDC on TRON. The directory carries USDT on eleven networks, including TRC20, but USDC stops at thirteen non-TRON chains. If your balance sits on TRON as USDT, moving to USDC means an extra swap or bridge before this choice even begins. What the thirteen share is only the ticker. (XMR to USDT exit)

At $100, every large chain pays about $6 less than its own curve. The 100-USDC quotes ranged from 0.15327033 XMR on Avalanche to 0.15595808 on Base, a 1.75% spread. Five of the six large-capable networks clustered between 0.15554677 and 0.15595808; Avalanche was the outlier. More useful is what each quote implies against the same network's 1,000 and 5,000 quotes. Those two fit a line of 0.001656229 XMR per USDC, or 603.78 USDC per XMR. At 100 USDC that line predicts 0.1656229 XMR before any deduction. Those five quotes were 0.1555–0.1560, so 5.8–6.1 USDC of value disappeared; Avalanche's 0.15327033 lost 7.5 USDC, and BSC's 0.15507067 lost 5.5 against its own, already worse, line. At 1,000 the gap is about $0.03; at 5,000 it is zero. This is not a miner fee. It is the one-route small-size quote tier. A follow-up test on Ethereum in the same window sharpened the edge: 105, 110 and 115 USDC still returned one route, 120 returned two; going from 115 to 120 added 4.35% principal and 10.47% output, because the $5 step lifted the whole ~$5.8 deduction. (how Monero fees work)

At $1,000, six networks converge and BSC does not. All six large-capable networks returned two routes and a quote between 1.656175 (Solana) and 1.656199 (Avalanche C-Chain) XMR — a 0.0015% spread, or 603.78 USDC per XMR. BSC returned one route and 1.63239026, which is 1.44% below the group. Its 1,000 and 5,000 quotes fit a different line: 0.001641155 XMR per USDC (609.33 USDC per XMR) with an intercept of −0.008765 XMR, about 5.34 USDC. So BSC's disadvantage is two things at once — a slope about 0.9% worse and a real fixed deduction — while the other six have neither at size. (SOL to XMR guide)

At $5,000, the same line holds. The six networks quoted 8.281092–8.281116 XMR; BSC quoted 8.19701098, 1.02% lower. The six small chains — Sui, Aptos, Monad, Sei, ARC and Asset Hub — did not return a number at all: the API answered HTTP 400 “amount above maximum” for both 1,000 and 5,000. That is not an outage; it is the ceiling, and the same 400 body carries the exact maximum.

The ceilings run from $711 to $162,508. In the same 06:05 snapshot, maxAmount was 162,508.03 USDC on Ethereum, 162,507.62 on Base, 162,443.92 on Solana and 162,443.85 on Arbitrum. Polygon stopped at 70,630.69, BSC at 21,180.51 and Avalanche C-Chain at 3,390.96. Sui, Aptos, Monad, Sei, ARC and Asset Hub all stopped between 711.23 and 712.52. The largest ceiling is 228.5 times the smallest. Minimums were almost uniform — 13.45 to 13.92 USDC on twelve networks, 15.18 on Avalanche — so the floor is a dollar rule, not a liquidity accident. (SOL to XMR guide)

The ceiling, not the rate, decides the network. Read the ceilings as a ladder. Up to about $711, all thirteen networks work. From $711 to $3,391, the six capped chains drop out and seven remain. From $3,391 to $21,181, Avalanche drops out and six remain. From $21,181 to $70,631, BSC drops out and five remain. From $70,631 to $162,508, only Ethereum, Base, Solana and Arbitrum can take the order. Above $162,508, none of the thirteen will quote. A 0.0015% rate difference is irrelevant if your amount does not fit the rail. (SOL to XMR guide)

The exit leg has its own spread. At 06:05 UTC, 1 XMR sold for 591.1065 USDC on Solana to 591.2969 on Base — a 0.032% spread across the five networks that answered the reverse query. Against the forward line of 603.78 USDC per XMR, 591.30 is 97.93%, so a full round trip costs about 2.07% before deposit gas. The symmetry around spot is clean: at $597.20 per XMR, the forward quote was 1.10% above spot and the reverse quote 0.99% below. Neither direction is a fee; both are the market spread built into the quote. (SOL to XMR guide)

Gas is noise; the tier is the cost. At 06:08 UTC an ERC-20 transfer cost about $0.0059 on Ethereum at 0.0438 gwei, $0.0022 on BSC at 0.05 gwei, $0.0016 on Polygon at 205.7 gwei, $0.0027 on Arbitrum at 0.0201 gwei, $0.0008 on Base at 0.006 gwei and $0.0013 on Avalanche at 2.57 gwei, assuming 63,000 gas; Solana charges 5,000 lamports plus 1,488,440 lamports of refundable rent, about $0.13 at SOL $86.59. None of that explains the $6 gap at $100 — that gap is the quote tier. The checklist: match the asset id to the network, read minAmount and maxAmount before sending, choose by ceiling if the amount is large, and use a fresh payout address. Quotes move; the page governs. At writing time (2026-11-09 06:04–06:08 UTC), these were the numbers. (SOL to XMR guide)