diff --git a/CHANGELOG.md b/CHANGELOG.md
index 592d95c5f1..1340ab1cba 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 
 ### Fixed
+- Add check when capital recovery period is zero and investment costs are 
+  non-zero in multi-stage GenX (#666)
 - Fix write_status with UCommit = WriteShadowPrices = 1 (#645)
 
 ## [0.3.7] - 2024-04-02
diff --git a/src/multi_stage/configure_multi_stage_inputs.jl b/src/multi_stage/configure_multi_stage_inputs.jl
index cb09042f03..5bdc025e89 100644
--- a/src/multi_stage/configure_multi_stage_inputs.jl
+++ b/src/multi_stage/configure_multi_stage_inputs.jl
@@ -21,26 +21,39 @@ NOTE: The inv\_costs\_yr and crp arrays must be the same length; values with the
 
 returns: array object containing overnight capital costs, the discounted sum of annual investment costs incured within the model horizon.
 """
-function compute_overnight_capital_cost(settings_d::Dict,inv_costs_yr::Array,crp::Array, tech_wacc::Array)
+function compute_overnight_capital_cost(settings_d::Dict,
+        inv_costs_yr::Array,
+        crp::Array,
+        tech_wacc::Array)
+
+    # Check for resources with non-zero investment costs and a Capital_Recovery_Period value of 0 years
+    if any((crp .== 0) .& (inv_costs_yr .> 0))
+        msg = "You have some resources with non-zero investment costs and a Capital_Recovery_Period value of 0 years.\n" *
+              "These resources will have a calculated overnight capital cost of \$0. Correct your inputs if this is a mistake.\n"
+        error(msg)
+    end
 
-	cur_stage = settings_d["CurStage"] # Current model
-	num_stages = settings_d["NumStages"] # Total number of model stages
-	stage_lens = settings_d["StageLengths"]
+    cur_stage = settings_d["CurStage"] # Current model
+    num_stages = settings_d["NumStages"] # Total number of model stages
+    stage_lens = settings_d["StageLengths"]
 
-	# 1) For each resource, find the minimum of the capital recovery period and the end of the model horizon
-	# Total time between the end of the final model stage and the start of the current stage
-	model_yrs_remaining = sum(stage_lens[cur_stage:end])
+    # 1) For each resource, find the minimum of the capital recovery period and the end of the model horizon
+    # Total time between the end of the final model stage and the start of the current stage
+    model_yrs_remaining = sum(stage_lens[cur_stage:end]; init = 0)
 
 	# We will sum annualized costs through the full capital recovery period or the end of planning horizon, whichever comes first
 	payment_yrs_remaining = min.(crp, model_yrs_remaining)
 
-	# KEY ASSUMPTION: Investment costs after the planning horizon are fully recoverable, so we don't need to include these costs
-	# 2) Compute the present value of investment associated with capital recovery period within the model horizon - discounting to year 1 and not year 0
-	#    (Factor to adjust discounting to year 0 for capital cost is included in the discounting coefficient applied to all terms in the objective function value.)
-	occ = zeros(length(inv_costs_yr))
-	for i in 1:length(occ)
-		occ[i] = sum(inv_costs_yr[i]/(1+tech_wacc[i]) .^ (p) for p=1:payment_yrs_remaining[i])
-	end
+    # KEY ASSUMPTION: Investment costs after the planning horizon are fully recoverable, so we don't need to include these costs
+    # 2) Compute the present value of investment associated with capital recovery period within the model horizon - discounting to year 1 and not year 0
+    #    (Factor to adjust discounting to year 0 for capital cost is included in the discounting coefficient applied to all terms in the objective function value.)
+    occ = zeros(length(inv_costs_yr))
+    for i in 1:length(occ)
+        occ[i] = sum(
+            inv_costs_yr[i] / (1 + tech_wacc[i]) .^ (p)
+            for p in 1:payment_yrs_remaining[i];
+            init = 0)
+    end
 
 	# 3) Return the overnight capital cost (discounted sum of annual investment costs incured within the model horizon)
 	return occ