Understanding what occurs after a buyer adds their signature to a Partially-Signed Bitcoin Transaction is essential for anyone using Horizon Market. The co-signing step represents the final approval needed to transform a transaction draft into a valid, broadcast-ready Bitcoin transfer. From that moment forward, the exchange process moves from preparation to settlement, with both Bitcoin and Counterparty assets transferring in a single, coordinated blockchain event.
Finalization and Settlement on Horizon Market
Once a buyer co-signs the PSBT, the transaction becomes fully authorized. Both required signatures are now embedded within the same Bitcoin transaction structure. At this stage, the transaction can be broadcast to the network for confirmation. Broadcasting may occur through the buyer’s wallet, the seller’s wallet, or another compatible node, depending on how the parties coordinate the final step.
The PSBT format itself was standardized through Bitcoin Improvement Proposals BIP 174, allowing multiple participants to sign a shared transaction without exposing private keys. After the second signature is added, the file transitions from a partially complete template into a finalized Bitcoin transaction eligible for inclusion in a block.
Immediate Transition to Atomic Execution
Following co-signature, the transaction’s atomic nature takes effect. The Bitcoin payment and the Counterparty asset transfer are locked together within the same blockchain operation. This means the seller’s BTC output and the buyer’s asset output are inseparable. If the transaction confirms, both transfers occur simultaneously, preventing any imbalance or partial completion.
This atomic execution eliminates the waiting period common in traditional marketplaces. There is no separate withdrawal request, escrow release, or secondary approval. Instead, confirmation on the Bitcoin blockchain serves as the definitive proof that both sides of the trade have settled.
Blockchain Confirmation and Network Validation
After broadcast, the transaction enters the Bitcoin mempool, where miners evaluate it for inclusion in the next block. Once confirmed, the blockchain permanently records the exchange. The BTC moves to the seller’s designated address, while the embedded Counterparty asset data ensures the buyer receives ownership of the agreed tokens.
Network confirmation provides cryptographic certainty. Because Horizon Market relies entirely on on-chain settlement, there is no internal ledger adjustment or off-chain accounting entry. The blockchain itself reflects the completed trade, offering transparency and verifiability to both participants.
Asset Delivery to the Buyer
From the buyer’s perspective, confirmation means the Counterparty asset is now under their control. Compatible wallets and blockchain explorers will reflect the updated asset balance after the transaction settles. Since the asset transfer was encoded within the same Bitcoin transaction, no additional steps are required.
This design ensures that asset delivery is automatic and trustless. The buyer does not need to contact the seller or request fulfillment. The blockchain enforces the exchange, guaranteeing that the asset and Bitcoin move in tandem.
Bitcoin Receipt by the Seller
Simultaneously, the seller receives the specified BTC amount directly into their wallet. Because the payment output was part of the signed transaction, it cannot be altered once both parties have approved it. The seller gains immediate assurance that the agreed funds are delivered as soon as the network confirms the block.
On the website horizon.market, users can monitor their transaction status, but the settlement itself occurs independently of the platform. Horizon Market does not custody funds or intervene after signatures are applied. The blockchain’s consensus mechanism completes the process autonomously.
No Intermediary Intervention Required
One of the defining outcomes after co-signing on Horizon Market is the absence of intermediary involvement. There is no clearinghouse reconciling balances or escrow service releasing payments. Instead, cryptographic signatures replace institutional trust. The trade is enforced by Bitcoin’s protocol rules rather than by a centralized authority.
This structure reduces counterparty risk and increases efficiency. Since both participants authorized the same transaction, there is no ambiguity about terms or amounts. The blockchain acts as the ultimate arbiter, ensuring the exchange executes precisely as signed.
A Seamless Conclusion to the Trade
In summary, once a buyer co-signs a PSBT on Horizon Market, the transaction becomes complete and ready for broadcast. Confirmation on the Bitcoin network finalizes the atomic swap, transferring BTC to the seller and Counterparty assets to the buyer in one unified step. This streamlined process demonstrates how Horizon Market uses collaborative transaction signing to achieve secure, trustless settlement without intermediaries, reinforcing its commitment to decentralized digital asset trading.