diff --git a/app/javascript/submission_form/form.vue b/app/javascript/submission_form/form.vue
index 761ad0f9..7a825141 100644
--- a/app/javascript/submission_form/form.vue
+++ b/app/javascript/submission_form/form.vue
@@ -23,7 +23,7 @@
   <FormulaFieldAreas
     v-if="formulaFields.length"
     :fields="formulaFields"
-    :readonly-values="readonlyConditionalFieldValues"
+    :readonly-values="readonlyFieldValues"
     :values="values"
   />
   <Teleport
@@ -454,7 +454,9 @@
             v-model="values[currentField.uuid]"
             :field="currentField"
             :submitter-slug="submitterSlug"
+            :fields="formulaFields"
             :values="values"
+            :readonly-values="readonlyFieldValues"
             @attached="attachments.push($event)"
             @focus="scrollIntoField(currentField)"
             @submit="!isSubmitting && submitStep()"
@@ -872,7 +874,14 @@ export default {
     },
     readonlyConditionalFieldValues () {
       return this.readonlyConditionalFields.reduce((acc, f) => {
-        acc[f.uuid] = (this.values[f.uuid] || f.default_value)
+        acc[f.uuid] = isEmpty(this.values[f.uuid]) ? f.default_value : this.values[f.uuid]
+
+        return acc
+      }, {})
+    },
+    readonlyFieldValues () {
+      return this.readonlyFields.reduce((acc, f) => {
+        acc[f.uuid] = isEmpty(this.values[f.uuid]) ? f.default_value : this.values[f.uuid]
 
         return acc
       }, {})
@@ -972,7 +981,10 @@ export default {
       return this.currentStepFields[0]
     },
     readonlyConditionalFields () {
-      return this.fields.filter((f) => f.readonly && f.conditions?.length && this.checkFieldConditions(f) && this.checkFieldDocumentsConditions(f))
+      return this.readonlyFields.filter((f) => f.conditions?.length)
+    },
+    readonlyFields () {
+      return this.fields.filter((f) => f.readonly && this.checkFieldConditions(f) && this.checkFieldDocumentsConditions(f))
     },
     stepFields () {
       const verificationFields = []
diff --git a/app/javascript/submission_form/payment_step.vue b/app/javascript/submission_form/payment_step.vue
index 6bbeb146..e4f2e232 100644
--- a/app/javascript/submission_form/payment_step.vue
+++ b/app/javascript/submission_form/payment_step.vue
@@ -92,10 +92,20 @@ export default {
       type: Object,
       required: true
     },
+    readonlyValues: {
+      type: Object,
+      required: false,
+      default: () => ({})
+    },
     values: {
       type: Object,
       required: true
     },
+    fields: {
+      type: Array,
+      required: false,
+      default: () => []
+    },
     submitterSlug: {
       type: String,
       required: true
@@ -109,6 +119,13 @@ export default {
     }
   },
   computed: {
+    fieldsUuidIndex () {
+      return this.fields.reduce((acc, field) => {
+        acc[field.uuid] = field
+
+        return acc
+      }, {})
+    },
     queryParams () {
       return new URLSearchParams(window.location.search)
     },
@@ -182,12 +199,23 @@ export default {
   },
   methods: {
     calculateFormula () {
-      const transformedFormula = this.field.preferences.formula.replace(/{{(.*?)}}/g, (match, uuid) => {
-        return this.values[uuid] || 0.0
+      const transformedFormula = this.normalizeFormula(this.field.preferences.formula).replace(/{{(.*?)}}/g, (match, uuid) => {
+        return this.readonlyValues[uuid] || this.values[uuid] || 0.0
       })
 
       return this.math.evaluate(transformedFormula.toLowerCase())
     },
+    normalizeFormula (formula, depth = 0) {
+      if (depth > 10) return formula
+
+      return formula.replace(/{{(.*?)}}/g, (match, uuid) => {
+        if (this.fieldsUuidIndex[uuid]) {
+          return `(${this.normalizeFormula(this.fieldsUuidIndex[uuid].preferences.formula, depth + 1)})`
+        } else {
+          return match
+        }
+      })
+    },
     async submit () {
       if (this.sessionId) {
         return fetch(this.baseUrl + '/api/stripe_payments/' + this.sessionId, {