diff --git a/lua/copilot/client.lua b/lua/copilot/client.lua
index 8c1111a1..5e2e17a0 100644
--- a/lua/copilot/client.lua
+++ b/lua/copilot/client.lua
@@ -97,6 +97,11 @@ function M.buf_attach(force)
     return
   end
 
+  local bufnr = vim.api.nvim_get_current_buf()
+  local bufname = vim.api.nvim_buf_get_name(bufnr)
+
+  M.config.root_dir = M.config.get_root_dir(require("lspconfig.util").path.sanitize(bufname), bufnr)
+
   local client_id = lsp_start(M.config)
   store_client_id(client_id)
 end
@@ -192,6 +197,7 @@ local function prepare_client_config(overrides)
       agent_path,
     },
     root_dir = vim.loop.cwd(),
+    get_root_dir = require("lspconfig.util").find_git_ancestor,
     name = "copilot",
     capabilities = capabilities,
     get_language_id = function(_, filetype)