A Transaction Cost Economics Analysis of Smallholder Integration into Modern Agri-Food Value Chains in South West Nigeria

The integration of smallholder farmers into modern agri-food value chains supplying supermarkets, food processors, and export markets has been proposed as a pathway to agricultural commercialisation and poverty reduction. However, transaction costs associated with contract compliance, quality verification, certification, and information asymmetry significantly affect which farmers integrate successfully and on what terms. This study applies transaction cost economics theory to analyse smallholder integration into modern agri-food value chains in South West Nigeria, focusing on cocoa, pineapple, and tomato chains in Oyo, Ondo, and Ogun States. The theoretical framework extends Williamson's transaction cost economics to the agricultural household context, incorporating household asset specificity, behavioural uncertainty, and institutional environment as key dimensions. A primary dataset of 350 farming households and 40 value chain enterprises was collected through structured surveys and value chain interviews. Transaction cost components were measured using time use records, transport cost diaries, and information search cost estimation instruments. A structural equation model was estimated to test the mediated relationship between transaction costs, integration decision, and welfare outcomes. Results indicate that asset specificity, particularly investments in certification and packaging equipment, was the strongest predictor of sustained integration. Incomplete contracting and measurement problems in quality assessment created hold-up problems for 42 percent of integrated farmers, reducing effective prices received. Institutional support through farmer organisations significantly reduced information search costs. The study contributes an empirically grounded transaction cost economics framework for value chain integration policy in the Nigerian agri-food sector. Keywords: transaction cost economics, value chain integration, smallholder, South West Nigeria, agri-food