Changenow is a Non-Custodial Swap Service Built Around One-Time Deposits

From one-time deposit instruction to wallet payout

The one-time deposit flow is the defining mechanism of Changenow: the service creates an order-specific payment instruction, waits for the selected network to confirm it, converts the asset through its liquidity connections, and broadcasts a separate payout transaction. The exchange page makes that sequence visible without requiring the user to open a trading account or maintain a service balance.

One created exchange accepts one deposit associated with one transaction ID. Classic-rate deposit monitoring lasts about 24 hours, while the fixed-rate flow gives the sender 10 minutes to transmit the quoted amount. Those windows govern deposit recognition and rate eligibility rather than end-to-end settlement, which also includes confirmation on the input chain and delivery over the output chain.

After the deposit is recognized, the order advances through three core processing phases: Confirming, Exchanging, and Sending to you. Confirmation belongs to the input blockchain, conversion belongs to the service layer, and final receipt belongs to the destination network. Retaining the order ID until the payout confirms preserves the clearest record of that entire sequence.

Setting the pair, network, and recipient before sending

The pair and address setup determines whether the output arrives on a usable network. An order requires four exact inputs - the source asset and network, amount, output asset and network, and recipient address - while a displayed memo or destination tag becomes a fifth routing field that must travel with the deposit.

Network labels matter even when tickers and address shapes look identical. ETH appears separately on Ethereum, Base, and Arbitrum One; USDT appears on rails including Ethereum under ERC-20, Tron under TRC-20, BNB Smart Chain under BEP-20, and Solana under the SPL Token standard. Selecting the ticker without selecting its ledger leaves the order incomplete.

An Ethereum-style address represents 20 bytes and appears as 40 hexadecimal characters, or 42 characters when the 0x prefix is included. EIP-55 adds a mixed-case checksum, yet the same address syntax still does not distinguish Ethereum from Base or Arbitrum One. XRP Ledger destination tags are 32-bit unsigned integers, Stellar Memo IDs are 64-bit unsigned integers, and Solana account addresses encode 32 bytes, so every auxiliary field must be copied with the address.

Classic and fixed-rate quotes run on different clocks

The two Changenow quote modes separate execution flexibility from payout certainty. A classic-rate quote remains an estimate until conversion, whereas a fixed-rate order preserves the displayed output when the deposit is sent within its 10-minute window and satisfies the order conditions.

Classic output moves with the executable market rate, available liquidity, route costs, and network charges. Fixed-rate pricing incorporates a reserve for market movement into the displayed rate, which explains why its receive amount differs from the classic estimate at the same moment. The choice concerns the value of certainty, not a promise that either mode finishes faster.

Two clocks therefore matter: the deposit window and blockchain settlement. Broadcasting within the quote window starts the payment, while network confirmation still follows the rules of Bitcoin, Ethereum, Solana, or whichever input chain carries the transfer. The order page separates those stages so a valid deposit does not look like an already completed conversion.

Where the received amount changes before payout

The received amount reflects four components: the executable asset rate, the service spread or fixed-rate reserve, relevant network charges, and any partner commission embedded by an integrated interface. Retail exchange costs appear inside the displayed receive estimate rather than as one separately itemized percentage. The sending wallet also charges its own input-chain transaction fee when it broadcasts the deposit.

The minimum displayed by the order is dynamic because the deposit must remain large enough to cover processing and network costs. A quote that worked earlier is therefore not reusable evidence of a later minimum. Large fixed-rate orders also face pair-specific caps, while most classic-rate pairs do not publish a universal maximum.

The published refund terms set a $50 processing charge plus network fees for specified deposit errors, while BCH sent to a supported SegWit BTC address requires at least $60 and carries a 15% charge with a $50 floor. Digital-asset extraction in eligible cases takes up to 20 business days, and an incorrectly deposited ERC-20 token refund may take up to 24 hours. These recovery charges are operational costs, not ordinary swap fees.

Temporary custody, irreversible transfers, and order failure states

The classic Changenow custody model transfers control twice: the user sends the input from a personal wallet, the service controls it during conversion, and the output returns to the designated wallet. "Non-custodial" describes the absence of a persistent exchange balance in this flow; it does not make the conversion atomic or remove the service-controlled interval.

Several failure states follow directly from that architecture. A deposit on the wrong network does not match the order, an omitted memo leaves a shared-address payment without its routing identifier, and a token with the wrong contract address remains unrecognized. A deposit worth less than the relevant network fee also leaves no practical amount to exchange or return.

Automated transaction screening may pause a selected order for identity verification, and the issued verification link remains valid for 3 days. Optional Pro and custody products use a different control model because they maintain an ongoing account relationship. For funds held in limited circumstances, the service terms restrict the stated storage period to 1 calendar year.

Cross-chain conversion without managing a bridge position

Cross-chain conversion is the primary use case for the one-time deposit design. A user holding native BTC can request ETH on Base, while someone holding USDT on Tron can request USDC on Solana, provided the exact pair and networks are available when the order is created. The payout arrives as the selected supported asset on its destination chain.

That mechanism serves portfolio rebalancing, network migration, and payments that require a particular asset and ledger. It also removes the intermediate steps of funding an exchange account, placing an order, withdrawing the result, and later closing an unused balance. The transaction ID becomes the temporary order record instead of an account ledger entry.

A swap is distinct from a blockchain bridge. A bridge transfers a representation of an asset between connected networks, frequently using locked or burned value and a corresponding wrapped or minted asset. The exchange route changes the asset, the network, or both, then settles a fresh payout from the service's available liquidity.

Brokered swaps, EVM aggregators, and native cross-chain pools

Wallet-routed alternatives change who controls the conversion funds and where the price forms. Uniswap executes through automated market maker pools on EVM networks, 1inch aggregates routes across on-chain liquidity, and THORChain coordinates native-asset swaps through cross-chain pools and threshold-signature vaults. Changelly and SimpleSwap resemble the deposit-to-payout service pattern more closely.

A deposit service fits a conversion between unrelated chains without connecting a wallet to a decentralized application. Uniswap and 1inch fit supported EVM routes where wallet-signed contract execution matters, while THORChain fits supported native cross-chain pools. Deposit-based alternatives deserve comparison by exact network labels, quote mode, deposit window, and refund rules rather than ticker alone.

APIs and partner tools behind the exchange widget

The integration layer explains why the same swap workflow appears inside third-party wallets and applications. Changenow launched its instant-exchange platform in September 2017, then expanded the consumer widget into mobile and business products. The interface remains an order creator, while the underlying system supplies pair data, estimates, deposit instructions, status transitions, and payout handling.

The published partner catalogue presents six connection formats: an API, widget, button, referral link, WordPress plugin, and Telegram bot. Its API limit is 1,800 requests per minute, equal to 30 requests per second under one key. A private API key is generated from a GPG public key, works with the exchange-management endpoint, and is issued once per business account without replacement.

For a one-off exchange, the practical sequence remains shorter than the integration stack: choose the destination network and wallet first, compare the two quote modes second, make one deposit third, and retain the transaction ID until the payout confirms. That order keeps the irreversible transfer aligned with the asset, chain, rate rule, and recipient chosen at order creation.