Improving load factor is relevant for shippers due to its potential in reducing both transport costs and emissions. The purpose is to structure shippers’ opportunities to increase load factor according to required and available capacity. A framework is developed from literature, and in-depth understanding is provided by three cases, with data mainly collected through semi-structured interviews. Shippers’ opportunities to increase load factor are structured per decreasing, increasing, or reallocating required or available capacity. Required capacity can be changed by adjusting number of items, item characteristics, and how items are combined. Available capacity can be changed by adjusting number and type of units. Changes that improved load factor are described in detail for each case. Load factor is calculated for the packaging and shipping levels. An approach that logistics managers can apply to identify opportunities relevant to their situations is presented. Findings are relevant to researchers within transport efficiency and green logistics.