diff --git a/lua/fude/preview.lua b/lua/fude/preview.lua
index 848dd4e..29c7296 100644
--- a/lua/fude/preview.lua
+++ b/lua/fude/preview.lua
@@ -38,6 +38,9 @@ function M.open_preview(source_win)
 	end
 
 	local preview_buf = vim.api.nvim_create_buf(false, true)
+	if content:sub(-1) == "\n" then
+		content = content:sub(1, -2)
+	end
 	local lines = vim.split(content, "\n", { trimempty = false })
 	vim.api.nvim_buf_set_lines(preview_buf, 0, -1, false, lines)
 
diff --git a/tests/fude/preview_integration_spec.lua b/tests/fude/preview_integration_spec.lua
index 4fbaa82..99c2ad1 100644
--- a/tests/fude/preview_integration_spec.lua
+++ b/tests/fude/preview_integration_spec.lua
@@ -6,7 +6,7 @@ describe("preview integration", function()
 	before_each(function()
 		config.setup({})
 		helpers.mock_diff({ ["source.lua"] = "source.lua" })
-		helpers.mock_base_content("base line 1\nbase line 2\nbase line 3")
+		helpers.mock_base_content("base line 1\nbase line 2\nbase line 3\n")
 	end)
 
 	after_each(function()
@@ -42,11 +42,49 @@ describe("preview integration", function()
 
 			assert.is_not_nil(config.state.preview_buf)
 			local lines = vim.api.nvim_buf_get_lines(config.state.preview_buf, 0, -1, false)
+			assert.are.equal(3, #lines)
 			assert.are.equal("base line 1", lines[1])
 			assert.are.equal("base line 2", lines[2])
 			assert.are.equal("base line 3", lines[3])
 		end)
 
+		it("handles base content without trailing newline", function()
+			helpers.mock_base_content("no trailing newline")
+
+			local buf = helpers.create_buf({ "current line 1" }, "source.lua")
+			local source_win = vim.api.nvim_get_current_win()
+			vim.api.nvim_win_set_buf(source_win, buf)
+
+			config.state.active = true
+			config.state.base_ref = "main"
+			config.state.scope = "full_pr"
+
+			preview.open_preview(source_win)
+
+			local lines = vim.api.nvim_buf_get_lines(config.state.preview_buf, 0, -1, false)
+			assert.are.equal(1, #lines)
+			assert.are.equal("no trailing newline", lines[1])
+		end)
+
+		it("preserves trailing blank lines in base content", function()
+			helpers.mock_base_content("line 1\n\n")
+
+			local buf = helpers.create_buf({ "current line 1" }, "source.lua")
+			local source_win = vim.api.nvim_get_current_win()
+			vim.api.nvim_win_set_buf(source_win, buf)
+
+			config.state.active = true
+			config.state.base_ref = "main"
+			config.state.scope = "full_pr"
+
+			preview.open_preview(source_win)
+
+			local lines = vim.api.nvim_buf_get_lines(config.state.preview_buf, 0, -1, false)
+			assert.are.equal(2, #lines)
+			assert.are.equal("line 1", lines[1])
+			assert.are.equal("", lines[2])
+		end)
+
 		it("enables diff mode on both windows", function()
 			local buf = helpers.create_buf({ "line 1", "line 2" }, "source.lua")
 			local source_win = vim.api.nvim_get_current_win()