diff --git a/esphome/components/sensor/__init__.py b/esphome/components/sensor/__init__.py
index 8abba17ff9..650f5ed826 100644
--- a/esphome/components/sensor/__init__.py
+++ b/esphome/components/sensor/__init__.py
@@ -770,7 +770,9 @@ async def calibrate_linear_filter_to_code(config, filter_id):
         linear_functions = [[k, b, float("NaN")]]
     elif config[CONF_METHOD] == "exact":
         linear_functions = map_linear(x, y)
-    return cg.new_Pvariable(filter_id, linear_functions)
+    return cg.new_Pvariable(
+        filter_id, cg.TemplateArguments(len(linear_functions)), linear_functions
+    )
 
 
 CONF_DEGREE = "degree"
diff --git a/esphome/components/sensor/filter.cpp b/esphome/components/sensor/filter.cpp
index 7b7a968f48..6a90a5af66 100644
--- a/esphome/components/sensor/filter.cpp
+++ b/esphome/components/sensor/filter.cpp
@@ -385,13 +385,10 @@ void HeartbeatFilter::setup() {
 
 float HeartbeatFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
 
-CalibrateLinearFilter::CalibrateLinearFilter(std::initializer_list<std::array<float, 3>> linear_functions)
-    : linear_functions_(linear_functions) {}
-
-optional<float> CalibrateLinearFilter::new_value(float value) {
-  for (const auto &f : this->linear_functions_) {
-    if (!std::isfinite(f[2]) || value < f[2])
-      return (value * f[0]) + f[1];
+optional<float> calibrate_linear_compute(const std::array<float, 3> *functions, size_t count, float value) {
+  for (size_t i = 0; i < count; i++) {
+    if (!std::isfinite(functions[i][2]) || value < functions[i][2])
+      return (value * functions[i][0]) + functions[i][1];
   }
   return NAN;
 }
diff --git a/esphome/components/sensor/filter.h b/esphome/components/sensor/filter.h
index 26a03acde5..cb4abd154a 100644
--- a/esphome/components/sensor/filter.h
+++ b/esphome/components/sensor/filter.h
@@ -528,13 +528,21 @@ template<size_t N> class OrFilter : public Filter {
   bool has_value_{false};
 };
 
-class CalibrateLinearFilter : public Filter {
+/// Non-template helper for linear calibration (implementation in filter.cpp)
+optional<float> calibrate_linear_compute(const std::array<float, 3> *functions, size_t count, float value);
+
+/// N is set by code generation to match the exact number of calibration segments.
+template<size_t N> class CalibrateLinearFilter : public Filter {
  public:
-  explicit CalibrateLinearFilter(std::initializer_list<std::array<float, 3>> linear_functions);
-  optional<float> new_value(float value) override;
+  explicit CalibrateLinearFilter(std::initializer_list<std::array<float, 3>> linear_functions) {
+    init_array_from(this->linear_functions_, linear_functions);
+  }
+  optional<float> new_value(float value) override {
+    return calibrate_linear_compute(this->linear_functions_.data(), N, value);
+  }
 
  protected:
-  FixedVector<std::array<float, 3>> linear_functions_;
+  std::array<std::array<float, 3>, N> linear_functions_{};
 };
 
 /// Non-template helper for polynomial calibration (implementation in filter.cpp)