diff --git a/app/controllers/letters_controller.rb b/app/controllers/letters_controller.rb
index 5e80efe..7b40f65 100644
--- a/app/controllers/letters_controller.rb
+++ b/app/controllers/letters_controller.rb
@@ -183,8 +183,6 @@ class LettersController < ApplicationController
       return
     end
 
-    indicium = USPS::Indicium.new(letter: @letter, payment_account: usps_payment_account)
-
     hcb_payment_account = current_user.hcb_payment_accounts.find_by(id: params[:hcb_payment_account_id])
 
     if hcb_payment_account.blank?
@@ -192,12 +190,31 @@ class LettersController < ApplicationController
       return
     end
 
-    service = HCB::IndiciumPurchaseService.new(indicium: indicium, hcb_payment_account: hcb_payment_account)
-    if service.call
-      redirect_to @letter, notice: "Indicia purchased successfully (charged to #{hcb_payment_account.organization_name})."
-    else
-      redirect_to @letter, alert: service.errors.join(", ")
+    indicium = USPS::Indicium.new(letter: @letter, payment_account: usps_payment_account)
+    cost_cents = (@letter.postage * 100).ceil
+
+    ActiveRecord::Base.transaction do
+      transfer_service = HCB::TransferService.new(
+        hcb_payment_account: hcb_payment_account,
+        amount_cents: cost_cents,
+        memo: "Theseus postage: #{@letter.public_id}",
+      )
+      transfer = transfer_service.call
+
+      unless transfer
+        redirect_to @letter, alert: transfer_service.errors.join(", ")
+        return
+      end
+
+      indicium.hcb_payment_account = hcb_payment_account
+      indicium.hcb_transfer_id = transfer.id
+      indicium.save!
+      indicium.buy!
     end
+
+    redirect_to @letter, notice: "Indicia purchased successfully (charged to #{hcb_payment_account.organization_name})."
+  rescue => e
+    redirect_to @letter, alert: "Purchase failed: #{e.message}"
   end
 
   private
diff --git a/app/models/letter/batch.rb b/app/models/letter/batch.rb
index 4abbce8..e7e6151 100644
--- a/app/models/letter/batch.rb
+++ b/app/models/letter/batch.rb
@@ -154,18 +154,46 @@ class Letter::Batch < Batch
     generate_labels(options)
   end
 
-  # Purchase indicia for all letters in the batch using a single payment token
-  # Requires hcb_payment_account to create a disbursement for the whole batch
   def purchase_batch_indicia(usps_payment_account, hcb_payment_account:)
     raise ArgumentError, "HCB payment account is required to purchase indicia" if hcb_payment_account.nil?
+    raise ArgumentError, "USPS payment account is required to purchase indicia" if usps_payment_account.nil?
 
-    service = HCB::BatchPurchaseService.new(
-      batch: self,
-      hcb_payment_account: hcb_payment_account,
-      usps_payment_account: usps_payment_account,
-    )
-    unless service.call
-      raise StandardError, service.errors.join(", ")
+    letters_needing_indicia = letters.select do |letter|
+      letter.postage_type == "indicia" && letter.usps_indicium.nil?
+    end
+
+    return if letters_needing_indicia.empty?
+
+    total_cost_cents = letters_needing_indicia.sum do |letter|
+      (letter.postage * 100).ceil
+    end
+
+    ActiveRecord::Base.transaction do
+      transfer_service = HCB::TransferService.new(
+        hcb_payment_account: hcb_payment_account,
+        amount_cents: total_cost_cents,
+        memo: "Theseus batch postage: #{letters.count} letters",
+      )
+      transfer = transfer_service.call
+      unless transfer
+        raise StandardError, transfer_service.errors.join(", ")
+      end
+
+      update!(
+        hcb_payment_account: hcb_payment_account,
+        hcb_transfer_id: transfer.id,
+      )
+
+      payment_token = usps_payment_account.create_payment_token
+      letters_needing_indicia.each do |letter|
+        indicium = USPS::Indicium.create!(
+          letter: letter,
+          payment_account: usps_payment_account,
+          hcb_payment_account: hcb_payment_account,
+          mailing_date: letter_mailing_date,
+        )
+        indicium.buy!(payment_token)
+      end
     end
   end
 
diff --git a/app/models/letter/instant_queue.rb b/app/models/letter/instant_queue.rb
index 1c3eab3..462e55e 100644
--- a/app/models/letter/instant_queue.rb
+++ b/app/models/letter/instant_queue.rb
@@ -90,18 +90,30 @@ class Letter::InstantQueue < Letter::Queue
           usps_payment_account = USPS::PaymentAccount.find(usps_payment_account_id)
           Rails.logger.info("Found USPS payment account #{usps_payment_account.id}")
 
-          indicium = USPS::Indicium.create!(
+          indicium = USPS::Indicium.new(
             letter: letter,
             payment_account: usps_payment_account,
             mailing_date: letter.mailing_date,
           )
-          Rails.logger.info("Created indicium #{indicium.id} for letter #{letter.id}")
+          Rails.logger.info("Created indicium for letter #{letter.id}")
+
+          cost_cents = (letter.postage * 100).ceil
 
           Rails.logger.info("Using HCB payment account #{hcb_payment_account.id} for letter #{letter.id}")
-          service = HCB::IndiciumPurchaseService.new(indicium: indicium, hcb_payment_account: hcb_payment_account)
-          unless service.call
-            raise "HCB payment failed: #{service.errors.join(', ')}"
+          transfer_service = HCB::TransferService.new(
+            hcb_payment_account: hcb_payment_account,
+            amount_cents: cost_cents,
+            memo: "Theseus postage: #{letter.public_id}",
+          )
+          transfer = transfer_service.call
+          unless transfer
+            raise "HCB payment failed: #{transfer_service.errors.join(', ')}"
           end
+
+          indicium.hcb_payment_account = hcb_payment_account
+          indicium.hcb_transfer_id = transfer.id
+          indicium.save!
+          indicium.buy!
           Rails.logger.info("Successfully bought indicium for letter #{letter.id}")
 
           letter.reload
diff --git a/app/services/hcb/batch_purchase_service.rb b/app/services/hcb/batch_purchase_service.rb
deleted file mode 100644
index b45ff88..0000000
--- a/app/services/hcb/batch_purchase_service.rb
+++ /dev/null
@@ -1,79 +0,0 @@
-class HCB::BatchPurchaseService
-  class DisbursementError < StandardError; end
-
-  attr_reader :batch, :hcb_payment_account, :usps_payment_account, :errors
-
-  def initialize(batch:, hcb_payment_account:, usps_payment_account:)
-    @batch = batch
-    @hcb_payment_account = hcb_payment_account
-    @usps_payment_account = usps_payment_account
-    @errors = []
-  end
-
-  def call
-    return failure("No HCB payment account provided") unless hcb_payment_account
-    return failure("No USPS payment account provided") unless usps_payment_account
-
-    letters_needing_indicia = batch.letters.select do |letter|
-      letter.postage_type == "indicia" && letter.usps_indicium.nil?
-    end
-
-    return true if letters_needing_indicia.empty?
-
-    total_cost_cents = estimate_total_cost_cents(letters_needing_indicia)
-
-    ActiveRecord::Base.transaction do
-      transfer = create_disbursement!(total_cost_cents)
-      batch.update!(
-        hcb_payment_account: hcb_payment_account,
-        hcb_transfer_id: transfer.id,
-      )
-
-      purchase_indicia_for_letters!(letters_needing_indicia)
-    end
-
-    true
-  rescue HCBV4::APIError => e
-    failure("HCB disbursement failed: #{e.message}")
-  rescue => e
-    failure("Batch purchase failed: #{e.message}")
-  end
-
-  private
-
-  def create_disbursement!(amount_cents)
-    hcb_payment_account.create_disbursement!(
-      amount_cents: amount_cents,
-      memo: "Theseus batch postage: #{batch.letters.count} letters",
-    )
-  end
-
-  def purchase_indicia_for_letters!(letters)
-    payment_token = usps_payment_account.create_payment_token
-
-    letters.each do |letter|
-      indicium = USPS::Indicium.create!(
-        letter: letter,
-        payment_account: usps_payment_account,
-        hcb_payment_account: hcb_payment_account,
-        mailing_date: batch.letter_mailing_date,
-      )
-      indicium.buy!(payment_token)
-    end
-  end
-
-  def estimate_total_cost_cents(letters)
-    letters.sum do |letter|
-      if letter.processing_category == "flat"
-        150
-      else
-        73
-      end
-    end
-  end
-
-  def failure(message)
-    @errors << message
-    false
-  end
-end
diff --git a/app/services/hcb/indicium_purchase_service.rb b/app/services/hcb/indicium_purchase_service.rb
deleted file mode 100644
index 0902f13..0000000
--- a/app/services/hcb/indicium_purchase_service.rb
+++ /dev/null
@@ -1,61 +0,0 @@
-class HCB::IndiciumPurchaseService
-  class DisbursementError < StandardError; end
-
-  attr_reader :indicium, :hcb_payment_account, :errors
-
-  def initialize(indicium:, hcb_payment_account:)
-    @indicium = indicium
-    @hcb_payment_account = hcb_payment_account
-    @errors = []
-  end
-
-  def call
-    return failure("No HCB payment account provided") unless hcb_payment_account
-    return failure("No letter attached to indicium") unless indicium.letter
-
-    estimated_cost_cents = estimate_cost_cents
-
-    ActiveRecord::Base.transaction do
-      transfer = create_disbursement!(estimated_cost_cents)
-      indicium.hcb_payment_account = hcb_payment_account
-      indicium.hcb_transfer_id = transfer.id
-      indicium.save!
-
-      indicium.buy!
-    end
-
-    true
-  rescue HCBV4::APIError => e
-    failure("HCB disbursement failed: #{e.message}")
-  rescue => e
-    failure("Purchase failed: #{e.message}")
-  end
-
-  private
-
-  def create_disbursement!(amount_cents)
-    hcb_payment_account.create_disbursement!(
-      amount_cents: amount_cents,
-      memo: disbursement_memo,
-    )
-  end
-
-  def estimate_cost_cents
-    letter = indicium.letter
-    base_cents = if letter.processing_category == "flat"
-      150
-    else
-      73
-    end
-    (base_cents * 1.0).ceil
-  end
-
-  def disbursement_memo
-    "Theseus postage: #{indicium.letter.public_id}"
-  end
-
-  def failure(message)
-    @errors << message
-    false
-  end
-end