A Systematic Literature Review on the Comparative Analysis between Green and Conventional Bonds

This systematic review compares green and conventional bonds across pricing (yield/greenium), liquidity, volatility, and credit risk. Using PRISMA, we searched Scopus, Web of Science, SSRN, JSTOR, EconLit, and Google Scholar (through June 2025), applied pre-specified inclusion criteria, and coded certification/second-party review, framework (ICMA GBP/SBP/SLBP), market segment, and region. Results show a small, context-dependent yield discount for green bonds; sustainable bonds exhibit similar or slightly weaker pricing effects. Liquidity differences are mixed but narrow with stronger disclosure and external reviews. Volatility is generally comparable or lower, and credit risk metrics are neutral to modestly favourable, especially for first, credibly certified issues. Overall, investors can add sustainability exposure at near-market terms, while issuers may achieve marginal cost-of-capital benefits when credibility is high. We highlight gaps in causal identification, emerging-market dynamics, and sustainability-linked bond performance, and outline implications for portfolio construction and regulation.