diff --git a/alembic/versions/567bfb019a87_add_last_sent_column_to_clins_and_pdf_.py b/alembic/versions/567bfb019a87_add_last_sent_column_to_clins_and_pdf_.py
new file mode 100644
index 00000000..e56997ee
--- /dev/null
+++ b/alembic/versions/567bfb019a87_add_last_sent_column_to_clins_and_pdf_.py
@@ -0,0 +1,29 @@
+"""add last_sent column to clins and pdf_last_sent to task_orders
+
+Revision ID: 567bfb019a87
+Revises: 0039308c6351
+Create Date: 2020-01-31 14:06:21.926019
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision = '567bfb019a87' # pragma: allowlist secret
+down_revision = '0039308c6351' # pragma: allowlist secret
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('clins', sa.Column('last_sent_at', sa.DateTime(), nullable=True))
+    op.add_column('task_orders', sa.Column('pdf_last_sent_at', sa.DateTime(), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('task_orders', 'pdf_last_sent_at')
+    op.drop_column('clins', 'last_sent_at')
+    # ### end Alembic commands ###
diff --git a/atst/models/clin.py b/atst/models/clin.py
index 2811bd6a..13a63cee 100644
--- a/atst/models/clin.py
+++ b/atst/models/clin.py
@@ -1,5 +1,13 @@
 from enum import Enum
-from sqlalchemy import Column, Date, Enum as SQLAEnum, ForeignKey, Numeric, String
+from sqlalchemy import (
+    Column,
+    Date,
+    DateTime,
+    Enum as SQLAEnum,
+    ForeignKey,
+    Numeric,
+    String,
+)
 from sqlalchemy.orm import relationship
 from datetime import date
 
@@ -29,6 +37,7 @@ class CLIN(Base, mixins.TimestampsMixin):
     total_amount = Column(Numeric(scale=2), nullable=False)
     obligated_amount = Column(Numeric(scale=2), nullable=False)
     jedi_clin_type = Column(SQLAEnum(JEDICLINType, native_enum=False), nullable=False)
+    last_sent_at = Column(DateTime)
 
     #
     # NOTE: For now obligated CLINS are CLIN 1 + CLIN 3
diff --git a/atst/models/task_order.py b/atst/models/task_order.py
index 789a7e3f..d6aa63f8 100644
--- a/atst/models/task_order.py
+++ b/atst/models/task_order.py
@@ -39,6 +39,7 @@ class TaskOrder(Base, mixins.TimestampsMixin):
 
     pdf_attachment_id = Column(ForeignKey("attachments.id"))
     _pdf = relationship("Attachment", foreign_keys=[pdf_attachment_id])
+    pdf_last_sent_at = Column(DateTime)
     number = Column(String, unique=True,)  # Task Order Number
     signer_dod_id = Column(String)
     signed_at = Column(DateTime)