Lexilio vs Spellbook: Construction Contract Review

Lexilio publishes this page. We have a commercial interest in the outcome, so we have restricted every statement about Spellbook to what Spellbook publishes on its own pages, with the date we checked it. Where Spellbook does not publish something, we say that rather than estimating it.

The short version. Spellbook is built for transactional lawyers and in-house legal teams and works principally inside Microsoft Word, reviewing, drafting and redlining commercial contracts across many industries. Lexilio is built for contractors' commercial teams working on construction contracts, including FIDIC, NEC, JCT and AIA forms with their bespoke amendments. It covers the whole commercial job on a contract: answering questions with citations, drafting and editing documents and spreadsheets, checking contracts against your own positions, and tracking obligations, notices, exposure and conflicts across a project. These are different products for different buyers. The right choice depends on who does the work and what they are reading.

Spellbook

Last checked: 29 October 2026. Sources: the Spellbook home page, pricing page and construction contract review guide, which that page records as last updated 27 September 2026.

Key features. Spellbook describes itself as a contract AI suite covering Review for redlining contracts and catching risks, Draft for drafting from scratch or from saved libraries, Ask for answers to questions about a document, Compare for comparing contracts to industry standards, and Playbooks for encoding a team's legal standards. It also lists Associate, described as a multi-document agent for working through multi-document matters, and an Autonomous Contract Management product offered on an early access basis. The pricing page groups the Word add-in and Associate together as the Spellbook Suite. Published integrations include Microsoft Word, Google Docs, Slack, OneDrive, SharePoint, Dropbox, Google Drive and iManage.

Strengths. The Word add-in is the centre of the product rather than an accessory to it, which matters if your negotiation happens in tracked changes. Spellbook's construction guide states that Spellbook integrates directly into Microsoft Word, enabling review without changing an existing drafting workflow. Drafting is a first-class capability: the same guide states that Spellbook offers targeted clause suggestions, spots inconsistencies and provides alternative language recommendations as you work in Word, and that it can draft an initial contract version and generate clauses and entire contract sections. Playbooks can be built in and custom made, and the pricing page lists a Playbook Build Service for in-house teams. On security, the home page lists SOC 2 Type II, HIPAA, GDPR and EU AI Act, states that zero data retention means its LLM providers never learn from, train on or store customer data, and refers to SSO, MFA, encryption and audit controls. The pricing page repeats SOC 2 Type II compliance and refers to Zero Data Retention agreements.

Limitations for construction standard forms. Spellbook publishes a construction contract review guide, and on that page states that Spellbook can review construction agreements, subcontracts, change orders, NDAs, construction management agreements and joint venture agreements, and that its AI is designed to handle provisions such as payment schedules, change order procedures, liability clauses, indemnities, insurance requirements and milestone dates. Read that alongside two things we did not find.

First, we found no reference to FIDIC, NEC or JCT on any Spellbook page we checked. Second, the AIA reference on that page is worth reading closely. The question posed is whether AI construction document review software handles AIA or ConsensusDocs, and the answer given is that modern AI construction document review tools are trained on industry-standard templates like AIA and ConsensusDocs. That is a statement about the category rather than a statement that Spellbook itself is trained on those forms. The same page answers a question about conflicting terms across subcontracts in the same general register, saying that advanced construction contract review software can compare a master agreement against multiple subcontracts. We are not treating either as a Spellbook product claim, because the pages do not phrase them that way. If AIA or ConsensusDocs coverage is decisive for you, ask Spellbook directly and get the answer in writing.

Separately, Spellbook's published industry solution pages cover Energy, Healthcare, Financial Services, Technology, Manufacturing, and Retail and Consumer Goods. Construction is not among them. Its published audience is law firms and in-house legal teams, and its home page describes the platform as being for transactional lawyers.

Best for. In-house legal functions and law firms reviewing and drafting general commercial contracts at volume, particularly teams whose work happens in Word and who want playbook consistency across NDAs, MSAs, vendor and supplier agreements. Spellbook's own customer references point the same way: its home page describes an engineering group using Spellbook to review supplier master services agreements across multiple countries.

Pricing. Not published. The pricing page states that pricing is structured around the number of team members on a licence and directs prospective customers to book a demo for personalised pricing. It states that a 7-day free trial is available for lawyers and legal teams, that extended trials may be available for larger organisations, and that free access is offered to academic institutions.

Lexilio

Last checked: 29 October 2026. Sources: Lexilio's live product and published pages for the platform, Contract Assistant, Playbooks, Projects, pricing and security.

Key features. Lexilio is a construction commercial intelligence platform for FIDIC, NEC, JCT and AIA contracts, including bespoke amendments and Particular Conditions. It has three working areas.

Contract Assistant answers questions about a contract with citations that open the source clause. It drafts and edits Word documents and spreadsheets in the same workspace: letters, clause rewrites, amendments, notices, registers and schedules. You edit them beside the conversation and export them. It reads redlined Word documents and turns tracked changes into a structured list of issues. It reviews from your side of the contract, using the party role you set.

Playbooks turn your negotiation positions, such as liability caps, payment terms, notice periods and indemnity language, into rules. Every contract is checked clause by clause. Each finding is reported as compliant, a deviation or missing, and each contract gets a scorecard. You can write rules one by one, import them, or have Lexilio build a playbook from your negotiation guidelines, standard terms or a contract you were happy with. Playbooks work in Contract Assistant and across a whole project. In a project, documents that have not changed since the last check are shown as up to date instead of being checked again.

Projects reads the main contract, subcontracts, variations (change orders) and specifications together. It extracts:

• obligations and deadlines;
• risks and opportunities, with financial exposure per risk;
• on Enterprise, a project total shown as a range with how many risks it covers;
• on Enterprise, conflicts between documents, such as a subcontract notice period shorter than the main contract allows.

Notices are drafted from the obligation that triggers them, and recorded when served with the date, method and who served them. Obligations, risks, conflicts and notices can be assigned to named team members. The full project report exports with a reviewer record.

Strengths. Construction is the whole product, so the output is written for quantity surveyors, commercial managers and cost managers rather than for lawyers. Playbooks answer the question that matters in practice: not what the contract says, but whether it is acceptable to you. Cross-document analysis and notice tracking address two expensive failures: flow-down gaps between a prime contract and its subcontracts, and missed notices during delivery. Assignment and the served-notice record mean a project's commercial record is kept by the team, with every step attributable.

Security. Lexilio publishes these commitments on its security page:

• customer contracts are never used to train AI models;
• data is stored on EU-region infrastructure;
• data is encrypted with AES-256 at rest and in transit;
• access is controlled by Owner, Admin, Member and Viewer roles, with access set per project;
• an immutable audit log records actions, and owners and admins can export it;
• Lexilio complies with UK and EU GDPR.

Full detail is on our security page.

Limitations. Lexilio works in its own web workspace, not as a Word add-in. If your team needs to negotiate inside the counterparty's own Word file, with suggestions appearing in that document, Lexilio does not work that way. Our coverage is construction contracts and the documents around them, so a team whose work is mostly NDAs, employment agreements and SaaS terms will get little from the construction analysis.

Best for. Quantity surveyors, commercial managers, cost managers and procurement teams at contractors and developers working on FIDIC, NEC, JCT or AIA contracts. It fits best where:

• incoming contracts must be checked against the company's own positions;
• a prime contract must be checked against a package of subcontracts;
• notices and deadlines must be tracked through delivery by a team.

Pricing. Published. Tiers and current figures are on the pricing page. Starter includes a 7-day trial (10 uploads); Professional includes a 14-day trial (20 uploads). A card is taken at signup, with no charge if you cancel before the trial ends. Enterprise starts immediately.

Comparison Table

Spellbook entries are from its own published pages, last checked 29 October 2026. Lexilio entries are from our live product and published pages on the same date. "Not stated" means we did not find it on the pages we checked, not that the capability is absent.

Where Spellbook Is the Better Choice

Your team negotiates inside Word itself. If the job is opening a counterparty's draft in Word, marking it up and sending it back, a tool that sits inside that document works within your process. Spellbook, on its own account, puts suggestions and alternative language directly into the document you are editing. Lexilio drafts and edits in its own workspace and exports.

Your portfolio is mostly general commercial agreements. If most of your contracts are NDAs, master services agreements, employment and supplier terms, Spellbook is built for that mix, with playbooks across it and published pages for six industries. Lexilio's construction analysis would not apply to most of that work.

Your procurement process requires a SOC 2 report. Spellbook publishes SOC 2 Type II compliance on both its home page and its pricing page. Lexilio does not publish a SOC 2 report. If your information security review treats a current SOC 2 report as a gate rather than a preference, that is a legitimate reason to choose a vendor that has one. Our published commitments are on the security page.

Where Lexilio Is the Better Choice

Your contracts are construction contracts with bespoke amendments. Lexilio reads FIDIC, NEC, JCT and AIA forms together with their Particular Conditions and amendment schedules, and reviews them from your side of the contract.

Acceptability matters more than summary. Playbooks check every incoming contract against your own commercial positions and score it, so the question answered is whether the contract is acceptable to you, not only what it says.

The risk sits between documents. Projects checks the main contract against its subcontracts and variations, and flags where flow-down breaks, such as notice periods, liability caps and payment terms that do not line up.

The work continues after signature. Obligations, deadlines, notices and exposure are tracked through delivery, assigned to named people, recorded when served, and exported as a full project report with an audit trail behind it.

Frequently Asked Questions

Does Spellbook support FIDIC, NEC or JCT contracts?

Spellbook does not state that it does on any page we checked, including its home page, pricing page and construction contract review guide, as at 29 October 2026. Its construction guide names AIA and ConsensusDocs, but in a sentence about AI construction document review tools as a category rather than about Spellbook specifically, so we are not reporting it as a Spellbook product claim. Spellbook's published industry pages do not include construction, and it describes its platform as being for transactional lawyers. If FIDIC, NEC or JCT coverage matters to your decision, ask Spellbook directly rather than relying on this page or on ours.

Does Lexilio have playbooks like Spellbook?

Yes. Lexilio Playbooks encode a contractor's own positions on liability caps, payment terms, notice periods and indemnity language, and check every contract against them clause by clause, with a scorecard per contract. You can write the rules yourself, import them, or have Lexilio build a playbook from guidelines, standard terms or a contract you were happy with. Spellbook describes playbooks for encoding legal standards across general commercial contracts, while ours are built around a contractor's commercial positions on construction contracts. Playbooks run in Contract Assistant and across every document in a project. See our Playbooks page.

Can Lexilio draft and edit documents?

Yes. Contract Assistant drafts and edits Word documents and spreadsheets in the workspace, including letters, clause rewrites, amendments, notices, registers and schedules, and exports them. The difference from Spellbook is where the editing happens: Spellbook works inside Microsoft Word, while Lexilio works in its own workspace with the contract, playbooks and project record alongside.

Can we use both?

Yes, and for some teams that is the sensible answer. The two products address different stages. A commercial team can use Lexilio to check incoming construction contracts against its playbooks, track the notice calendar and check flow-down across the subcontract package, while the legal function uses Spellbook inside Word for the general commercial agreements around the project, such as NDAs and supplier terms. Nothing in either product prevents this, though you would be paying for two licences and should check that the overlap is worth it.

How much does each cost?

Spellbook does not publish price figures. Its pricing page states that pricing is based on the number of team members on a licence and asks prospective customers to book a demo, and it states that a 7-day free trial is available. Lexilio publishes its tiers and current figures on the pricing page. We are not quoting Spellbook numbers here because they are not public, and we are not going to estimate them.

Which one should a commercial team choose?

If the documents in front of you are construction contracts, and the questions are whether they are acceptable against your own positions, what the amendments changed, where the subcontracts fall short of the main contract, and which notices are due, Lexilio is built for that and Spellbook does not claim to be. If your work is mostly general commercial agreements negotiated inside Word, Spellbook is built for that. The practical test: take a contract you have already reviewed by hand, one where you found something significant, and run it through any tool you are considering, including ours. Check whether it found what you found, whether it found anything you missed, and whether it explained the commercial consequence or only flagged the clause.

What This Page Does Not Cover

• We have not tested Spellbook on a FIDIC, NEC, JCT or AIA contract. Nothing here is a performance comparison; every Spellbook statement comes from its published pages on 29 October 2026.
• We have not independently verified Spellbook's security certifications. Its trust portal is the place to request the documentation.
• We have not reproduced Spellbook's published time-saving or customer statistics, because they are the vendor's own measurements.
• Vendor pages change. Check the linked pages on the day you read this.

This is a general guide, not legal advice.

WRITTEN BY

Lexilio Editorial

Construction Commercial Intelligence