What is a Principal Token?
A principal token (PT) is one of two components created when a yield-bearing asset undergoes yield stripping. The principal token represents the right to claim the underlying asset at a specific maturity date, without any of the yield generated during the holding period. PTs trade at a discount to the underlying asset, with the discount representing the implied fixed yield an investor earns by holding the token to maturity.
Principal tokens bring the concept of zero-coupon bonds to DeFi. Just like a zero-coupon bond that pays face value at maturity but no interest along the way, a principal token pays out the underlying asset at maturity with the return coming purely from the purchase discount.
How it Works
When a yield-bearing asset like stETH enters a yield stripping protocol, it's divided into principal and yield components for a specific maturity date. The principal token holder gives up all yield until maturity in exchange for a guaranteed claim on the underlying.
The PT price reflects the market's implied yield to maturity. If a PT for stETH with 1-year maturity trades at 0.95 ETH per PT, the implied fixed yield is approximately 5.26% annualized (buying at 0.95 and receiving 1.00 at maturity). As maturity approaches, the PT price converges toward 1:1 with the underlying.
Principal tokens can be freely traded before maturity. If yields fall, PTs become more valuable (the fixed yield you locked in becomes more attractive). If yields rise, PTs lose value relative to holding the yield-bearing asset directly. This creates opportunities for rate speculation and hedging.
At maturity, PTs are redeemable 1:1 for the underlying asset. The redemption mechanism varies by protocol, typically involving burning the PT to receive the underlying from the protocol's reserves.
For users seeking stable, predictable returns, buying PTs locks in a known outcome regardless of future yield fluctuations. This is particularly valuable for treasury management, liability matching, or conservative yield strategies.
Practical Example
A treasury manager needs to deploy 1,000 ETH worth of assets with a guaranteed return in 6 months. They purchase PT-stETH trading at 0.98 stETH per PT with 6-month maturity. They spend 980 stETH to acquire 1,000 PT-stETH. At maturity, they redeem for exactly 1,000 stETH, earning a fixed 2.04% over 6 months (approximately 4.08% annualized), regardless of whether stETH yields during the period were higher or lower.
Why it Matters
Principal tokens enable fixed-yield strategies in an ecosystem dominated by variable rates. They provide predictability for conservative investors, hedging tools for those wanting to reduce rate exposure, and arbitrage opportunities for sophisticated traders. Understanding PTs is essential for anyone seeking guaranteed returns in DeFi. Fensory tracks principal token prices across maturities and underlying assets, helping you compare fixed yields and identify the most attractive opportunities for stable returns.