Is an electronic signature valid?

Yes. Electronic signatures are legally valid in interstate commerce under the ESIGN Act (15 U.S.C. ch. 96) and in most states under UETA; ensure intent, consent, attribution, and retrievable record retention to meet legal tests.

When is notarization required for addenda?

Most simple addenda do not require notarization. Notarization or witnesses may be necessary for particular instruments (real estate deeds, powers of attorney) or per contract clause; check state notary rules and contract language before assuming notarization is required.

Can change orders be signed electronically?

Yes. Under the federal ESIGN Act (15 U.S.C. ch. 96) and state UETA laws, properly executed electronic change orders are enforceable when the legal tests are met: signer intent, consent to electronic records, signer attribution, and reliable record retention for reproduction.

How should signer identity be verified?

Use multi-factor authentication, email plus SMS codes, identity proofing, or government ID verification for higher-risk addenda. Keep audit logs with IP addresses, timestamps, and authentication method to support attribution if a signature is disputed.

What about HIPAA or PHI in addenda?

If an addendum contains protected health information, ensure the eSignature vendor supports HIPAA compliance and execute a Business Associate Agreement (BAA). Retain records per 45 CFR §164.530(j) and follow organizational privacy policies.

What retention period applies to addenda?

Retain executed addenda for the contract term plus at least three years to align with IRS baseline; extend retention for tax, SEC, or HIPAA records as required (IRC §6501(a); 45 CFR §164.530(j)). Consult counsel for state-specific rules.

Electronic Signature
Templates
Miscellaneous
Project Proposal Addendum

Project Proposal Addendum

This template is fully customizable. Edit the text, fill out the fields, and send it for signature. Give it a try!

PROJECT PROPOSAL ADDENDUM

This Project Proposal Addendum (this Addendum) is made effective as of by and between Client Name: ("Client") and Contractor Name: ("Contractor").

RECITALS

WHEREAS, Client and Contractor previously entered into a proposal identified as Proposal Reference: dated (the Proposal); and

WHEREAS, the parties desire to amend certain terms of the Proposal as set forth in this Addendum and to confirm that, except as expressly modified herein, the Proposal remains in full force and effect.

AMENDMENTS

The Proposal is hereby amended as follows. Checked items indicate sections expressly modified by this Addendum:

Scope of Work Schedule / Timeline Price / Payment Terms Other (specify below)

If Other, describe:

SCOPE OF WORK

The Scope of Work set forth in the original Proposal is amended as follows. The Contractor shall perform the following tasks and deliverables in accordance with the specifications and schedule set forth below:

Amended Scope of Work:

PAYMENT TERMS

The parties agree that all payment terms in the Proposal are modified as follows:

Adjusted Total Fee: Payment Schedule and Milestones: Invoice Payment Terms:

Invoices are due within days of invoice date. Late payments will incur a late fee of % per month or the maximum permitted by law, whichever is less.

TERM AND TERMINATION

This Addendum commences on Start Date: and continues until End Date: unless earlier terminated in accordance with the Proposal or this Addendum.

Either party may terminate this Addendum for convenience upon providing written notice to the other party at least prior to the intended termination date. Termination for cause shall be permitted immediately upon written notice if the other party materially breaches any obligation and fails to cure such breach within thirty (30) days following receipt of written notice specifying the breach.

CONFIDENTIALITY

The parties acknowledge that certain information exchanged in connection with the Proposal and this Addendum may be Confidential Information. Each party shall maintain the confidentiality of such information using at least the same degree of care it uses to protect its own confidential information but not less than a reasonable standard of care. Confidential Information excludes information that is (a) already known to the receiving party without restriction, (b) becomes publicly available through no fault of the receiving party, (c) independently developed by the receiving party without use of the disclosing party's Confidential Information, or (d) required to be disclosed by law, provided the disclosing party is given prompt notice and allowed to seek protective measures.

GOVERNING LAW

This Addendum shall be governed by and construed in accordance with the laws of the State of , without regard to conflict of laws principles.

ENTIRE AGREEMENT

Except as expressly modified by this Addendum, the Proposal remains unchanged and in full force and effect. This Addendum, together with the Proposal, constitutes the entire agreement between the parties with respect to the subject matter hereof and supersedes all prior and contemporaneous agreements, understandings, negotiations and discussions, whether oral or written. No amendment to this Addendum will be effective unless in writing and signed by both parties.

MISCELLANEOUS

If any provision of this Addendum is held to be invalid or unenforceable, the remaining provisions will remain in full force and effect. Waiver of any breach must be made in writing and shall not constitute a waiver of any other or subsequent breach.

Client

Printed Name:

By:

Date:

Contractor

Printed Name:

By:

Date:

What a Project Proposal Addendum Is

Project Proposal Addendum is a short, written amendment to an existing project proposal that documents changes in scope, schedule, deliverables, pricing, or terms after the original proposal was issued. It operates as an attachment or amendment that becomes part of the governing proposal or contract once agreed and signed by authorized parties. Use clear references to the original proposal by date and identifier, describe specific changes, state effective dates, and record approvals and signatures. The addendum helps avoid misunderstandings and creates an auditable record of negotiated modifications.

Why Use an Addendum Instead of Rewriting the Proposal

Use a Project Proposal Addendum to document agreed changes without redrafting the entire proposal. It preserves contractual continuity, clarifies responsibilities, limits disputes, and provides an audit trail for approvals, billing adjustments, and schedule updates, which supports compliance and project governance.

Who Typically Prepares and Signs Addenda

Common users include project managers, procurement teams, and client account managers who manage scope and pricing changes.

Project managers document scope changes, delivery dates, and incremental budgets with signature records.
Procurement and purchasing teams track approved change orders and supplier cost adjustments.
Clients and account leads confirm approved revisions, timelines, and billing terms in writing.

Small business owners, legal counsel, and contract administrators also rely on addenda for version control and audit readiness.

Step-by-Step: Complete a Project Proposal Addendum

Follow these steps to complete a Project Proposal Addendum accurately and produce a signed, enforceable amendment.

01

Reference the Original: Cite proposal ID, date, and relevant clauses.
02

Describe Changes: Specify scope, schedule, deliverables, pricing, and rationale.
03

Obtain Approvals: Send to authorized parties for review, redlines, and sign-off.
04

Execute Addendum: Sign dated addendum; attach to original proposal and distribute.

Essential Data Elements

Addendum Title: Exact title and amendment number

Effective Date: Enter as MM/DD/YYYY date format

Reference Proposal: Original proposal ID and date

Parties: Full legal names and addresses

Change Description: Clear scope and pricing details

Signatures: Signer name, title, date

Core Elements of a Professional Addendum

A professional Project Proposal Addendum combines clear identification, precise change language, defined timelines, cost impacts, approvals, and attachments so it integrates seamlessly with the original contract.

Identification

Include addendum title, amendment number, original proposal reference, and effective date so parties can unambiguously link the document to the governing proposal and internal tracking codes if used.

Change Details

Provide numbered descriptions for each modification, explaining what is changing, why, and any acceptance criteria or performance metrics that apply to deliverables and milestones explicitly.

Financials

State precise pricing adjustments, payment schedules, invoicing references, taxes, and any retainers or credits, including how costs affect existing payment terms and billing dispute resolution procedures.

Timeline

Specify new or revised delivery dates, milestone deadlines, notice periods, and the effective date for each change; indicate dependencies that affect schedule risk and escalation contacts.

Approvals

List individuals authorized to approve the addendum, include titles and signature blocks, and note any internal approval steps or delegated authority limits with dates and record identifiers.

Attachments

Attach revised schedules, scope matrices, change order forms, cost breakdowns, and any supporting emails or drawings referenced by the addendum, and label each exhibit with a letter and short description.

How Electronic Routing Works for an Addendum

This routing overview shows how to prepare, route, sign, and archive a Project Proposal Addendum using electronic workflows.

Upload Document: Upload final addendum draft as PDF or DOCX.
Place Fields: Add signature, date, and initial fields for each signer.
Set Authentication: Choose signer verification: email, SMS code, or identity proofing.
Send & Track: Send invites, monitor status, and capture audit trail.

Recommended Online Workflow Settings

Recommended online settings to configure an efficient addendum workflow and maintain auditability across systems and records.

Field	Configuration
Signing Order	Sequential approvers sign in defined order.
Authentication	Email + SMS OTP; enable higher proof for vendor changes.
Reminder Schedule	Auto-reminders at 3 and 7 days; escalate if unresponsive.
Archive Location	Save signed PDFs to contract repository and cloud storage.

Platform and Security Requirements

Electronic completion requires a compliant eSignature provider, secure storage, and defined authentication policies to maintain enforceability and audit logs.

File Formats: PDF and DOCX preferred formats.
Integrations: Salesforce, NetSuite, Microsoft 365 integrations.
Security: TLS and AES-256 encryption.

eSignature Pricing and Feature Comparison

Compare baseline eSignature pricing and feature availability for common plans; signNow appears first per comparison standards.

	signNow	DocuSign	Adobe Sign	PandaDoc	HelloSign
Starting Price	$8/user/mo	$15/user/mo	$14/user/mo	$19/user/mo	$15/user/mo
Free Trial	7-day trial	Varies by plan	Varies by plan	Varies by plan	Varies by plan
Bulk Send	Yes	Yes	Yes	Yes	No
Audit Trail	Yes	Yes	Yes	Yes	Yes
HIPAA Compliant	Yes	Yes	Yes	No	No
Envelope Cap	No cap	100 envelopes/user/year	Varies by plan	Varies by plan	Varies by plan

Consequences of an Incorrect or Incomplete Addendum

Ambiguous Scope: Leads to disputes and work scope creep

Invalid Signatures: May be unenforceable without proper authorization

Missing Dates: Billing and liability windows unclear

Incorrect Parties: Wrong legal entity risks contract voiding

Failure to Attach: Referenced exhibits not included

Regulatory Noncompliance: HIPAA or procurement rules breached

Common Preparation Errors to Avoid

Failing to reference the original proposal precisely causes confusion over which terms are modified and can invalidate linkage between documents during audits or disputes.
Using vague language such as 'as agreed' or 'reasonable adjustment' leaves financial and schedule obligations open to interpretation and increases litigation risk.
Not obtaining signatures from authorized signatories or failing to record dates can render the addendum unenforceable against non-signing parties.
Attaching inconsistent exhibits or failing to update cost schedules causes billing disputes and delays in project execution and invoicing.

Who Has Authority to Sign

Project Manager

The project manager often initiates the addendum to document scope or schedule changes and must coordinate approvals. However, they may lack final contracting authority; financial or legal sign-off is typically required from an authorized officer or delegated approver.

Authorized Signatory

An authorized signatory (executive, CFO, or legal designee) holds legal power to bind the organization to amended terms. Confirm delegation limits and signature authority in internal policies before execution to avoid later challenges to enforceability.

Two Practical Examples

Real-world examples show how addenda resolve scope changes, adjust budgets, and preserve project timelines without reissuing full contracts.

Client Scope Increase

A services firm needed to add additional features to a live project after client request and before the next billing cycle.

Addendum documented scope, cost, and new deadlines.
The firm circulated the addendum for electronic signatures, recorded approvals, and updated the project schedule. Clear pricing and acceptance criteria prevented a billing dispute and accelerated authorization for the change order.

Vendor Cost Adjustment

A construction subcontractor discovered material cost increases after bidding and needed to amend the proposal to reflect updated unit rates and allowances.

Addendum adjusted pricing and delivery terms.
Authorized representatives signed the addendum with notarization where contract provisions required it; invoices were revised, and change orders tracked in the project management system, which preserved payment schedules and reduced payment disputes.

Best Practices for Accurate and Efficient Completion

Practical tips improve accuracy, shorten approval cycles, and reduce legal exposure when preparing an addendum.

Use clear, numbered change items and references

Break multiple modifications into numbered lines, reference original clause numbers, and include precise acceptance criteria. This reduces ambiguity and makes it straightforward to apply changes to scope of work, invoices, and schedules during execution and audit review.

Confirm signer authority and delegation limits

Verify signers are authorized under internal delegation policies; attach delegation evidence if necessary. Ensure signatures are from legal entities named in contracts and that electronic authentication methods meet company risk and compliance standards.

Document version control and secure storage procedures

Store executed addenda in a centralized contract repository with searchable metadata, include original proposal references, and configure retention policies consistent with regulatory and corporate rules. Keep tamper-evident PDFs and audit logs for future disputes or compliance checks.

Use eSign platforms with compliance features

Choose an eSignature provider that produces tamper-evident signed PDFs, detailed audit trails, and relevant compliance reports. For healthcare or regulated procurements, confirm BAA availability and strong authentication options, and document this in procurement policy.

Frequently Asked Questions

Common questions about validity, signing authority, notarization, and secure storage for Project Proposal Addenda, including eSubmission considerations and audit trail expectations.

Need help? Contact support

Is an electronic signature valid?
Yes. Electronic signatures are legally valid in interstate commerce under the ESIGN Act (15 U.S.C. ch. 96) and in most states under UETA; ensure intent, consent, attribution, and retrievable record retention to meet legal tests.
When is notarization required for addenda?
Most simple addenda do not require notarization. Notarization or witnesses may be necessary for particular instruments (real estate deeds, powers of attorney) or per contract clause; check state notary rules and contract language before assuming notarization is required.
Can change orders be signed electronically?
Yes. Under the federal ESIGN Act (15 U.S.C. ch. 96) and state UETA laws, properly executed electronic change orders are enforceable when the legal tests are met: signer intent, consent to electronic records, signer attribution, and reliable record retention for reproduction.
How should signer identity be verified?
Use multi-factor authentication, email plus SMS codes, identity proofing, or government ID verification for higher-risk addenda. Keep audit logs with IP addresses, timestamps, and authentication method to support attribution if a signature is disputed.
What about HIPAA or PHI in addenda?
If an addendum contains protected health information, ensure the eSignature vendor supports HIPAA compliance and execute a Business Associate Agreement (BAA). Retain records per 45 CFR §164.530(j) and follow organizational privacy policies.
What retention period applies to addenda?
Retain executed addenda for the contract term plus at least three years to align with IRS baseline; extend retention for tax, SEC, or HIPAA records as required (IRC §6501(a); 45 CFR §164.530(j)). Consult counsel for state-specific rules.

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