Stephen and Martine Batchelor have been offering meditation retreats on secular Buddhism since 2011. Listed below are several of their retreats:

Secular Buddhist Retreat (Gaia House)

These talks given in 2019 focus on seeking a practice of meditation that is secular in orientation but framed by Buddhist ethical and philosophical values. Exploring the role of mindfulness in embracing the suffering of life, letting go of the dictates of reactivity, experiencing the calm and clarity of spaciousness, and cultivating creative engagement as a way of being in the world.

https://dharmaseed.org/retreats/4293

Sǒn Retreat (Gaia House)

Based on that followed in the Sŏn (Zen) Buddhist tradition of Korea these talks  in 2019 look at seeking a balance between the calm of open awareness and a focus of deep inquiry into the nature of our lives through the question (kungan / koan) ‘What is this?’ Equal emphasis has been given to traditional instructions and contemporary interpretation of the tradition.

https://dharmaseed.org/retreats/4214

An Introduction to Secular Buddhism

A series of talks given over thirteen days in March 2012 at Sine Cera Retreat Centre in Australia by Martine and Stephen Batchelor

https://dharmaseed.org/retreats/1593/