The best RFP & DDQ response software in 2026
There is no single best RFP tool. The right one depends on your size, your budget, and whether you care more about persuasive writing or verified accuracy. Here are the leading options for RFPs, DDQs, and security questionnaires this year, with who each is for. We make one of them, Diligio, and we have tried to be fair about where the others are stronger.
Responsive (formerly RFPIO)
the enterprise incumbentBest for: Large enterprise bid teams with deep integration needs
The enterprise incumbent, compared with a flat-rate, verification-first alternative.
Pricing: Custom quote; ~$14k/yr reported (range $7k to $28k)
Diligio vs ResponsiveLoopio
the mid-market workflow favouriteBest for: Mid-market teams that want a polished content library and workflow
A polished library and workflow, compared with a flat-rate, verification-first alternative.
Pricing: Custom quote; from ~$20k/yr reported + add-ons
Diligio vs LoopioAutogenAI
the generative bid-writing engineBest for: Teams whose priority is persuasive, long-form bid and tender writing
Generative bid writing, compared with grounded, verification-first answering.
Pricing: Custom quote; premium tier (not published)
Diligio vs AutogenAIArphie
the AI-native newcomerBest for: Modern, AI-native teams comfortable with project-based pricing
Two modern, AI-native tools, compared on verification, pricing, and data residency.
Pricing: Custom quote; project-based (not published)
Diligio vs ArphieDiligio
that's usBest for: Verified accuracy and a flat, published price
One model drafts each answer from your knowledge base, a second independent model verifies it against your sources, and weak answers are withheld rather than guessed. SSO and agent/API access are included.
Pricing: $7,499 flat per year, published.
How to choose
Beyond the shortlist, four questions tend to decide it: how the AI prevents wrong answers, whether the price is published and flat or seat-based with add-ons, where your data is stored, and what is included versus sold as an upgrade. The comparison hub walks through each, and the guides cover the underlying processes.
Frequently asked questions
What is the best RFP software in 2026?
There is no single best tool; it depends on your needs. Responsive (formerly RFPIO) suits large enterprise bid teams, Loopio suits mid-market teams that want a polished library, AutogenAI suits persuasive long-form bid writing, and Arphie and Diligio are modern AI-native options. Diligio is built around verified accuracy at a flat $7,499 a year.
What is the most affordable RFP software?
Most tools in this category price by custom quote and by seat, so the real total varies a lot. Diligio publishes a flat $7,499 a year that already includes the AI, SSO, and API access, which makes it one of the easier options to budget for and compare.