Pre-funding cross-border payouts means depositing money with a bank or provider, in the payout currency or in a stablecoin, before the payouts are due, so each one is drawn from a balance already in place. It costs the return the idle balance could earn, FX movement on foreign balances, refill fees, account upkeep and staff time.
Why cross-border payouts end up pre-funded
Someone has to hold the destination currency before a recipient can be paid in it, and the paying company usually puts it there first. The waiting money can sit in local accounts the company opens in each country, in a balance held by a payment provider, or in a stablecoin wallet that converts to local currency only when a payout runs. The first two hold destination currency in advance; the third holds USDC (a dollar stablecoin, covered in what USDC is) and moves into the destination currency at send time, so the idle balance is in dollars.
Spread and per-transaction fees are covered in how stablecoin payout fees are built.
Lumx works the third way. The wallet keeps its balance between operations, which the docs call a prefunded wallet, and payouts go to destinations registered under that customer. Lumx's "no pre-funding" means something narrower than a zero balance: the customer parks no capital in settlement (nostro) accounts abroad before a transaction, because conversion and settlement happen when the transaction starts.
How big does a pre-funded balance need to be?
Balance per currency = daily payout volume x coverage days
The three parts of coverage days. The starting values are a planning default.
Part | What it measures | How to set it |
Refill lead time | Calendar days from deciding to top up until the money is usable | The slowest funding rail you use, with cut-offs and weekends |
Payout cycle gap | Days between payout runs, because a full run must be on hand | 1 for daily runs, up to 7 for weekly runs |
Safety buffer | Extra days for volume spikes and a refill that arrives late | Start at 1 or 2 days and raise it only where late funding has happened |
A team that refills by ACH (a US bank transfer that settles in business days) needs two days of refill lead time. With a weekly run and a one-day buffer, that covers ten days of volume.
In a Lumx wallet, the number to size is the stablecoin balance. A payout larger than the balance fails with an insufficient-balance error, so the float has to be in the wallet before the request goes out.
Funding lead times by rail decide the coverage days
Refill lead time is the part of coverage days a company can change without changing its business, because it depends on the funding rail. Pix (Brazil's instant payment system), SPEI (Mexico's interbank transfer system) and Faster Payments (the UK's real-time bank transfer network) have no cut-off and run every day. Business-day rails have cut-offs, and a later request waits for the next business day.
Cut-offs and settlement targets published by Lumx for processing on each rail, read on November 1, 2026. They are processing targets, not commitments.
Currency | Rail | Cut-off (local time) | Settlement target |
BRL | Pix | None | Instant, 24/7/365 |
MXN | SPEI | None | Instant, 24/7/365 |
GBP | Faster Payments | None | Instant, 24/7/365, up to £1M per payment |
EUR | SEPA | None | Real-time scheme, or SEPA Credit Transfer on the same or next business day |
USD | ACH | 2:00 PM ET | 1 to 2 business days |
USD | FEDWIRE | 3:00 PM ET | Same business day, typically within hours |
USD | SWIFT | 3:00 PM ET | 1 to 5 business days |
A weekend matters more than the headline time. An ACH transfer submitted on a Friday after 2:00 PM ET misses the cut-off, is processed on Monday and takes one to two business days, so the money could be usable only on Tuesday or Wednesday.
On Lumx, a funding deposit is an on-ramp that moves through AWAITING_FUNDS, TRANSFERRING_FIAT, TRADING, TRANSFERRING_STABLECOIN and SUCCESS, and the wallet is usable when the onramp.success webhook fires. Pix and SPEI settle instantly on the rail, 24/7/365, and the stablecoin is credited to the wallet within about 5 minutes. Inbound USD timing also depends on the sender's bank and its cut-offs. With on-demand on-ramps, each deposit must match an on-ramp created in advance with the exact amount, and a deposit that lands after it expires is refunded to the sender on the same rail. An autoconversion rule is the alternative: deposits are matched to the rule, not to a pre-created amount.
What a pre-funded balance costs in a year
The five annual cost lines of a pre-funded balance.
Cost line | Formula | What drives it |
1. Cost of capital | Balance x annual cost of capital | Coverage days and the rate you use |
2. FX allowance | Foreign-currency balance x expected adverse move | Volatility and the size of non-dollar balances |
3. Refill fees | Refills per year x fee per refill | Number of currencies and refill frequency |
4. Account upkeep | Accounts x annual fees and compliance work | Number of countries |
5. Operations time | Hours per week x 52 x loaded hourly cost | Forecasting, top-ups and checking balances |
Total annual cost is the sum of the five lines. Divide by annual payout volume and multiply by 10,000 to get basis points, the unit a provider quote is written in. Cost of capital is what the money would otherwise earn or save, such as a credit line rate or a hurdle rate. It is an assumption you choose, not a yield on any balance.
With Lumx, the destination-side lines shrink because the customer opens no local account in each destination country. Lines 1 and 5 are still yours to price.
A worked example: a Brazilian PSP paying out in three currencies
Every number below is an assumption for clean arithmetic, not Lumx data, a quote or a client. A Brazilian PSP pays out 2,400,000 USD a month: 1,000,000 in dollars, 900,000 in Mexican pesos and 500,000 in euros. That is 28,800,000 USD a year, or 80,000 USD a day. It holds ten days of coverage in each currency: two days of ACH refill lead time, a weekly run and a one-day buffer.
The balance is 800,000 USD. Cost of capital is 6% a year and the FX allowance on non-dollar balances 2% a year, both assumptions. Refills are 3 currencies x 52 weeks = 156 transfers at 5 USD, there are 3 accounts at 600 USD a year, and operations take 6 hours a week at 40 USD an hour.
Cost line | Calculation | Annual cost (USD) |
Cost of capital | 800,000 x 6% | 48,000 |
FX allowance | 466,667 x 2% | 9,333 |
Refill fees | 156 x 5 | 780 |
Account upkeep | 3 x 600 | 1,800 |
Operations time | 6 x 52 x 40 | 12,480 |
Total | 72,393 | |
Cost in basis points | 72,393 / 28,800,000 x 10,000 | About 25 bps |
First, shorten coverage without changing the model. The PSP keeps local-currency balances but refills every business day, holding one day of volume: 80,000 USD. It funds pesos by SPEI, euros by SEPA real-time and dollars by FEDWIRE, and the one-day figure assumes the dollar transfer goes out before the 3:00 PM ET cut-off. Capital costs 4,800 USD, the FX allowance on 46,667 of non-dollar balance 933 USD, and 780 refills (3 currencies x 260 business days) at 5 USD cost 3,900 USD. Upkeep and operations time stay at 1,800 and 12,480 USD, for 23,913 USD, about 8 bps.
Then the same PSP holds a one-day USDC float that its Pix funding keeps topped up. The FX allowance, refill fees and destination upkeep fall to zero, capital stays at 4,800 USD and operations time drops to two hours a week, 4,160 USD, for 8,960 USD, about 3 bps.
The same PSP under three setups, in basis points of payout volume.
Setup | Coverage | Total (USD a year) | Basis points |
Local-currency balances, weekly refills | 10 days | 72,393 | About 25 |
Local-currency balances, daily refills (SPEI, SEPA real-time, FEDWIRE before 3:00 PM ET) | 1 day | 23,913 | About 8 |
USDC float, one day of volume | 1 day | 8,960 | About 3 |
Shorter coverage accounts for about 17 of the 22 bps saved and the change of model for the other 5. Platform fees, per-transaction fees and conversion spread are excluded from all three totals and must be added from the provider quote. A route whose fees and spread run more than 5 bps above the daily-refill local-currency setup erases the model's saving. The dollar position held between converting reais and paying out is not priced here.
Lumx's wallet is the third setup. The PSP deposits reais by Pix, Lumx converts the deposit and credits the wallet in USDC, and each payout is an off-ramp from that wallet to the recipient's destination. See converting reais into USDC. The pairs have pages: USDC to BRL, BRL to USDC, USDC to MXN and MXN to USDC.
Coverage days move the result most, then the capital rate. At a 6% rate, 20 days of coverage costs about 129,700 USD a year, 45 bps, against about 25 bps at 10 days, a saving of 20 bps. Raising the rate from 6% to 10% at 20 days adds 22 bps, so halving coverage saves about as much as cutting the capital rate by four points. Multi-entity planning: automating corporate treasury.
The Lumx lever is the funding rail, since the payout side is already local. The wallet is usable once onramp.success fires, so a Pix or SPEI deposit does not have to be the slowest part of coverage days.
FX exposure on the idle balance
A foreign-currency balance revalues every day it sits: a peso balance of 300,000 USD equivalent that loses 2% over a year costs 6,000 USD before a payout uses it. A stablecoin float changes the currency of the exposure instead of removing it, so a small float keeps the exposure small. At send time, a locked rate closes the gap between quote and execution for a short window.
Lumx locks a rate for 30 seconds, 1 minute or 5 minutes, with no fee at 30 seconds and a fee at the longer windows. Its exchangeRateId is passed on the off-ramp, and an expired lock needs a new rate. A standing autoconversion rule that converts deposits to stablecoin always converts at market and does not accept a locked quote.
Ways to shrink the balance, starting with the slowest rail
I would size the float to the slowest funding rail the company uses, not to average daily volume, and I would refill in small steps over the fastest rail available instead of in one large wire. The risk of running dry is set by the single slowest delivery, so one slow weekly wire can force the whole balance up.
On Lumx, an autoconversion rule is the standing version of a small, frequent refill. Set once on a BRL, MXN, USD, EUR or GBP account, it converts every matching deposit to USDC or USDT and delivers it to the wallet with no per-deposit API call.
What are the alternatives to pre-funding, and what risk does the balance carry?
Three ways to avoid holding the full balance in advance, and what each one shifts.
Alternative | Balance the company holds | Who carries the credit risk | What drives the cost |
Post-funding, settlement credit or provider-fronted liquidity | Little or none before the payout | The provider, until the company settles | Credit limits, collateral, and a price built into fees or spread |
Credit line | Drawn only when needed | The lender | Interest on the drawn amount plus any commitment fee |
Nostro or correspondent account | A standing balance in each currency at the correspondent | The company, against the correspondent bank | The idle balance plus account fees |
None of these removes the cost, it moves it. The balance itself carries risk too. Money held with a bank or provider is exposure to that holder: if the account is frozen or the holder fails, the money waits with it. A stablecoin float adds two more: the issuer's token can trade below a dollar for a while, and whoever controls the keys controls the money. A float of about one day of volume keeps all three small.
On Lumx, the balance sits in a custodial wallet provisioned with the customer, held as USDC or USDT on Ethereum, Polygon, Base or Tron (Stellar is used only for the BRL to USDC on-ramp). BitGo, which carries insurance, is the custodian. Each customer's wallet is fully segregated, with no omnibus account, so balances mix neither with other customers' nor with Lumx's own. The balance is stablecoin, not a deposit, because Lumx is not a bank. The holder exposure above still applies, so the float stays near one day of volume.
When pre-funding is the wrong tool, and when it is still right
Funding at send time is the wrong choice when payouts must land at 2 a.m. on a Sunday and the company funds by ACH. Pre-funding is right when payouts must clear even if funding is late, as with payroll.
Pre-funding is the wrong choice for a team with steady volume and a real-time funding rail that spends hours a week topping up accounts, because it pays line 5 of the cost table for a buffer it does not need. Stablecoins move working capital from several destination-currency balances into one stablecoin balance, which still has to exist when a payout runs.
What funding a payout looks like on Lumx
Lumx is stablecoin payments infrastructure for businesses that move money between Latin America and the rest of the world: one API to collect, hold, convert, and pay out in BRL, MXN, COP, USD, EUR, and GBP or in USDC and USDT, over local rails such as PIX, SPEI, PSE, Bre-B, ACH, FEDWIRE, SEPA, and Faster Payments, with SWIFT and on-behalf-of payments and collections (POBO and COBO) in USD, EUR, and GBP, plus named virtual accounts, custodial wallets, and KYB/KYC built in.
The balance sits in a custodial wallet provisioned with the customer. Funding arrives as a local-currency deposit that Lumx converts and credits to that wallet, or as stablecoin sent in from elsewhere. A payout is an off-ramp that debits the wallet and converts to local currency on the recipient's rail, so the customer holds no reais, pesos or euros ahead of time. Lumx's pricing is built on transparent FX on locked quotes, no pre-funding, which is the nostro point above, not an empty wallet: a payout still debits the customer's stablecoin wallet, which must hold the balance when the request goes out.
An off-ramp moves through TRANSFERRING_STABLECOIN, TRADING, TRANSFERRING_FIAT and SUCCESS, with a webhook at each change. Rail cut-offs come from the Lumx payment rail cut-off times page, read on November 1, 2026. Coverage is on the coverage page, the payout side in global payments, and reais to pesos is the kind of path a stablecoin corridor describes.
Verified on November 1, 2026. Operational context, not legal, tax, or investment advice.
Cover photo: Tim Mossholder on Unsplash.
What does pre-funding cross-border payouts mean for a payments team?
The company puts money in the payout currency, or in a stablecoin, with a bank or provider before the payouts run, and draws each payout from that balance. On Lumx, that balance is stablecoin in the customer's custodial wallet, converted to local currency on the recipient's rail.
How do you work out the cost of pre-funding?
Add five annual lines (capital, FX allowance, refill fees, account upkeep, staff time), divide by annual payout volume and multiply by 10,000 for basis points. With Lumx, the destination-side lines shrink.
How much should a payout team hold in a pre-funded balance?
Daily payout volume times coverage days, per currency, where coverage days is refill lead time plus payout cycle gap plus a safety buffer. A Lumx payout larger than the wallet balance fails.
Does paying out in stablecoins remove pre-funding?
It removes the destination-currency balances but not the need for a balance, because the stablecoin float has to exist when the payout runs. On Lumx, an autoconversion rule can refill the wallet.
Does the idle balance carry FX risk?
Yes: a foreign-currency balance revalues while it sits, and a stablecoin float moves the exposure to the currency that funded it. A locked quote closes the gap at send time.
