smith6jt-cop Crypto Pair Fee Optimization - Research Notes
Experiment Overview
| Item | Details |
|---|---|
| Date | 2026-01-01 |
| Goal | Determine if crypto-to-crypto trading is advantageous vs crypto-to-fiat given Alpaca fee schedule and risk factors |
| Environment | Alpaca Crypto LLC, Fee schedule as of Aug 2023 |
| Status | Success |
Context
When rebalancing crypto portfolios or rotating between assets, there are two approaches:
- Crypto-to-USD route: Sell asset A for USD, buy asset B with USD (2 trades)
- Crypto-to-crypto route: Trade asset A directly for asset B (1 trade)
The question: Does Alpaca's fee structure favor one approach over the other?
Key Finding: Fee Structure is Identical
Per docs/rules_and_fees/AlpacaCryptoLLCFeeDisclosure.pdf, Alpaca uses the same maker/taker fees regardless of pair type:
| Tier | 30D Volume (USD) | Maker | Taker |
|---|---|---|---|
| 1 | $0 - 100K | 0.15% | 0.25% |
| 2 | $100K - 500K | 0.12% | 0.22% |
| 3 | $500K - 1M | 0.10% | 0.20% |
| 4 | $1M - 10M | 0.08% | 0.18% |
| 5 | $10M - 25M | 0.05% | 0.15% |
| 6 | $25M - 50M | 0.02% | 0.13% |
| 7 | $50M - 100M | 0.02% | 0.12% |
| 8 | $100M+ | 0.00% | 0.10% |
No per-trade fee advantage exists between pair types.
Verified Advantage: Trade Count Reduction
The only fee advantage comes from reducing the number of trades:
| Scenario | Crypto-to-USD Route | Crypto-to-Crypto Route | Savings |
|---|---|---|---|
| Rotate ETH → BTC | ETH→USD + USD→BTC = 2×0.25% = 0.50% | ETH→BTC = 0.25% | 50% |
| Rebalance 3 assets | Up to 6 trades | Up to 3 trades | 50% |
# Fee calculation for portfolio rotation
def calculate_rotation_fees(num_assets: int, fee_rate: float = 0.0025) -> dict:
"""Compare fees for crypto rotation strategies."""
# Via USD: sell all to USD, buy new positions
usd_route_trades = num_assets * 2 # sell + buy for each
usd_route_fee = usd_route_trades * fee_rate
# Via crypto pairs: direct swaps where available
crypto_route_trades = num_assets # direct swaps
crypto_route_fee = crypto_route_trades * fee_rate
return {
'usd_route_trades': usd_route_trades,
'usd_route_fee_pct': usd_route_fee * 100,
'crypto_route_trades': crypto_route_trades,
'crypto_route_fee_pct': crypto_route_fee * 100,
'savings_pct': (1 - crypto_route_fee / usd_route_fee) * 100
}
When Crypto-to-Crypto is Advantageous
- Portfolio rebalancing - Rotating between crypto assets you intend to hold
- Stablecoin parking - Using USDC/USDT pairs to avoid USD conversion delays
- Tax strategy - Potentially avoiding USD realization events (jurisdiction-dependent, consult tax advisor)
When Crypto-to-USD is Better
- Profit realization - Converting to USD for withdrawal/spending
- Risk-off moves - USD doesn't fluctuate while waiting to re-enter
- Simpler accounting - USD basis is clearer for tax reporting
- Wider liquidity - USD pairs typically have tighter spreads
Failed Attempts (Critical)
| Attempt | Why it Failed | Lesson Learned |
|---|---|---|
| Assuming crypto pairs have lower fees | Fee schedule is identical per trade | Advantage is only in trade count reduction |
| Looking for spread differences in docs | Alpaca doesn't publish spread data | Would need live testing to compare actual execution costs |
Risk Considerations
# Risk factors for crypto-to-crypto pairs
double_volatility_exposure: true # Both sides of trade can move
liquidity_variance: "USD pairs typically deeper"
spread_risk: "Exotic pairs may have wider spreads"
implementation_complexity: "Requires broker/backtest updates"
Available Alpaca Crypto Pairs
# Base currencies for crypto-to-crypto
BTC_pairs: [BCH, ETH, LTC, UNI]
USDT_pairs: [AAVE, BCH, BTC, DOGE, ETH, LINK, LTC, SUSHI, UNI, YFI]
USDC_pairs: [AAVE, AVAX, BAT, BCH, BTC, CRV, DOGE, DOT, ETH, GRT, LINK, LTC, SHIB, SKY, SUSHI, UNI, XTZ, YFI]
USD_pairs: "20+ assets including all USDC/USDT options plus XRP"
Implementation Notes
Current codebase trades crypto/USD only (e.g., BTC/USD). To implement crypto-to-crypto:
- Update
alpaca_trading/trading/broker.pyto handle non-USD quote currencies - Modify backtest infrastructure for multi-base accounting
- Add fee calculation that tracks the "credited side" denomination
- Consider liquidity/spread modeling for exotic pairs
Key Insights
- Fee percentages are identical across all pair types on Alpaca
- The only fee advantage is reducing trade count (50% savings on rotations)
- Crypto-to-crypto exposes you to volatility on both sides of the trade
- Stablecoin pairs (USDC/USDT) offer a middle ground: crypto liquidity with USD-like stability
- Implementation requires non-trivial changes to broker and backtest systems
References
docs/rules_and_fees/AlpacaCryptoLLCFeeDisclosure.pdf(local)- Alpaca Crypto Fees Documentation
- Alpaca Crypto Coin Pair FAQ
- Alpaca Crypto Trading Documentation