Pay-to-Script-Hash (P2SH)

Pay-to-Script-Hash, or P2SH, is a Bitcoin output type, activated by BIP 16 in April 2012, that locks coins to the hash of a script rather than to a key. Its addresses begin with 3. The spender reveals the full script, called the redeem script, and satisfies its conditions only when the coins move, so complex arrangements cost the sender nothing extra.

Why it matters

P2SH shifted the burden of complexity from payer to payee. Before it, sending to a multisig arrangement required the sender to construct an unusual transaction; after it, any wallet could pay a 3 address exactly like any other. That single change made multisignature custody commercially practical, and P2SH became the foundation for escrow, corporate treasuries and early payment channels. It also improved privacy modestly, since the script stays hidden until spend time.

In the gold vs bitcoin debate

P2SH marks the moment bitcoin ownership stopped meaning one key, one owner. Committee control, escrow and vault-like policies became native features of the asset, functions gold can only obtain through legal contracts layered on custodians. When SegWit and later Taproot arrived, they inherited and refined this pattern, but the 2012 upgrade is where programmable custody began at scale.