Custom apps, portals & UI extensions: 8 HubSpot partners to consider
Eight HubSpot partners for Custom apps, portals & UI extensions: Elixir, engaging.io, Aptitude 8, OneMetric, HubBase, Hypha, Niswey, Struto. Tier…
Extending HubSpot with business-specific interfaces, apps, data models and portals.
| Agency | HQ | Evidence |
|---|---|---|
| Elixir | Belgium-registered (Elixir Solutions BV); offices in Brussels, Munich, Cologne, Paris, Amsterdam and Stockholm | Engineering service offering |
| engaging.io | North Sydney, Australia (LinkedIn) | Named case study |
| Aptitude 8 | New York, USA (Built In; other directories differ) | HubSpot directory capabilities |
| OneMetric | Offices in New York, London, Dubai and Gurugram (no HQ labelled) | Named case study listing |
| HubBase | Remote (HubSpot listing) | Service offering with client testimonial |
| Hypha | Syosset or Glen Cove, New York, USA (sources differ) | Provider service offering |
| Niswey | New Delhi, India; additional offices in Goa and the United States (its newsroom) | Provider announcement |
| Struto | Horsham, England (LinkedIn, G2) | Provider service offering |
Shortlisted
Elixir
HubSpot tier: Elite, reported by the provider
HubSpot engineering practice explicitly covers custom extensions and quote/deal execution capabilities.
HQBelgium-registered (Elixir Solutions BV); offices in Brussels, Munich, Cologne, Paris, Amsterdam and Stockholm
FoundedNot stated
TeamNot stated
Named clientsArtemyn
Partners & badgesHubSpot Elite Solutions Partner (tier reported by the provider); SAP certified partner; ElixirSync SAP integration product
Services
What stands out
- Names HubSpot integration with SAP S/4HANA explicitly (ElixirSync)
- Salesforce-to-HubSpot migration case for an industrial business (Artemyn)
- Engineering practice covers custom extensions and quote execution
Research before choosing
- Request a comparable client reference and confirm proposed delivery team.
- Founding year, headcount and headquarters are not stated on the pages we checked
- Request a completed native Revenue Hub CPQ reference
- Request a matching S/4HANA deployment and object-level reference
Source: Engineering service offeringFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
engaging.io
HubSpot tier: Elite, per HubSpot directory
Mortgage Choice story documents a dual-portal HubSpot ecosystem, custom interfaces and integrations.
HQNorth Sydney, Australia (LinkedIn)
Founded2009 (LinkedIn)
Team11 to 50 (LinkedIn); 35+ in an older report
Named clientsLPW, Mortgage Choice
Partners & badgesHubSpot Elite Solutions Partner (HubSpot directory); JAPAC Partner of the Year 2025; 5-star HubSpot directory rating from 81 reviews
Services
What stands out
- Financial-sector examples: LPW wealth management and Mortgage Choice
- Five years of a dual-portal HubSpot ecosystem for Mortgage Choice
- 5-star HubSpot directory rating from 81 reviews
Research before choosing
- Request a comparable client reference and confirm proposed delivery team.
- Headcount differs by date (11 to 50 vs 35+)
- A joint venture led to a rebrand as Engaging Partners; confirm the contracting entity
- Request a comparable client reference
Source: Named case studyFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
Aptitude 8
HubSpot tier: Elite, reported by the provider
Directory documents custom development, extensibility and technical architecture engagements.
HQNew York, USA (Built In; other directories differ)
Founded2019 (its site); 2020 (directories)
Team50+ full-time employees (its site)
Named clientsHappyCo, Blue Ridge Risk Partners, OrangeDot
Partners & badgesHubSpot Elite Solutions Partner (tier reported by the provider); largest technical consulting team of any HubSpot partner (company-reported)
Services
What stands out
- Technical team that is 100% US-based full-time staff (company-reported)
- Case library covering migration, Salesforce integration and insurance integration
- HubSpot-hosted healthcare sessions led by its team
Research before choosing
- Request a comparable client reference and confirm proposed delivery team.
- Its Elite tier is provider-reported; HubSpot directory results we saw did not confirm it, so check the directory
- Headquarters and founding year differ by source
- Several cases are listings or anonymized; request references
Source: HubSpot directory capabilitiesFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
OneMetric
HubSpot tier: Elite, per HubSpot directory
Published Giift work is listed as a custom partner portal in HubSpot.
HQOffices in New York, London, Dubai and Gurugram (no HQ labelled)
FoundedNot stated
Team150+ HubSpot, RevOps and DevOps experts; 750+ customers serviced (company-reported)
Named clientsPearson, Ventrata, C&C Consulting, The Buzzlab
Partners & badgesHubSpot Elite Partner; Salesforce partner; Google Partner; ISO 27001
Services
What stands out
- HubSpot Elite Solutions Partner, with CRM implementation, integration, migration and onboarding accreditations on HubSpot's directory
- Published case studies with results: Qashio (+63% target attainment) and Tata Communications (+35% Tier 1 account engagement in 60 days)
- Applied AI example documented in HubSpot's customer showcase (Incentivio), with human approval on outreach
Research before choosing
- Request the full Giift architecture and portal reference for matching requirements.
- Customer counts (750+), team size (150+ experts) and SOC 2 Type II are company-reported; ask for evidence
- Founding year and headcount not stated
- Pricing not published
Source: Named case study listingFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
HubBase
Custom portal implementation includes API-driven quote/payment interactions.
HQRemote (HubSpot listing)
FoundedNot stated
TeamNot stated
Named clientsNot stated on the pages we checked
Partners & badgesHubSpot Gold Solutions Partner (HubSpot listing)
Services
What stands out
- HubSpot custom integrations, workflow optimization and customer-portal development.
- Custom portal implementation includes API-driven quote/payment interactions.
Research before choosing
- Confirm a comparable implementation reference and delivery team before selection.
- Broader integration capability; the cited source does not establish this exact connector implementation. Request an exact-platform client reference, architecture and support plan.
- Relevant technical service capability. Confirm comparable production work, technical ownership and ongoing support.
- Request a comparable client reference and confirm the delivery team
Source: Service offering with client testimonialFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
Hypha
HubSpot development, migrations, integrations and tailored quoting/workflow tools.
HQSyosset or Glen Cove, New York, USA (sources differ)
Founded2002 (as Morey Creative Studios)
TeamUnder 49 (DesignRush)
Named clientsNot stated on the pages we checked
Partners & badgesHubSpot Diamond-level partner (HubSpot listing)
Services
What stands out
- Provider identifies manufacturing among its industry specializations.
- Healthcare-specific HubSpot website migrations and integration offering.
- HubSpot development, migrations, integrations and tailored quoting/workflow tools.
Research before choosing
- Relevant technical service capability. Confirm comparable production work, technical ownership and ongoing support.
- Confirm a comparable implementation reference and delivery team before selection.
- Broader integration capability; the cited source does not establish this exact connector implementation. Request an exact-platform client reference, architecture and support plan.
- Request a comparable client reference and confirm the delivery team
Source: Provider service offeringFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
Niswey
HubSpot tier: Diamond, reported by the provider
HubSpot implementation, education specialization and custom application development.
HQNew Delhi, India; additional offices in Goa and the United States (its newsroom)
Founded2011
TeamNot stated
Named clientsVeracross and Moodle integrations (its own work)
Partners & badgesHubSpot Diamond partner; 2026 HubSpot Higher Education industry specialist badge (its newsroom)
Services
What stands out
- HubSpot implementation, education specialization and custom application development.
- Vira product provides AI-assisted WhatsApp responses connected to HubSpot.
Research before choosing
- Relevant technical service capability. Confirm comparable production work, technical ownership and ongoing support.
- Sector shortlist supported by the cited offering or client listing. Validate the same business model, region and project scope.
- Relevant technical service capability. Confirm comparable production work, technical ownership and ongoing support.
- Request a comparable client reference and confirm the delivery team
Source: Provider announcementFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
Shortlisted
Struto
HubSpot integration orchestration, customer portals and AI-enabled CRM extensions.
HQHorsham, England (LinkedIn, G2)
Founded2011
Team11-50 (LinkedIn)
Named clientsNot stated on the pages we checked
Partners & badgesHubSpot Elite partner (LinkedIn); Diamond on Clutch
Services
What stands out
- Frank & Lenny case documents a financial-services CRM migration.
- Dedicated HubSpot–NetSuite integration offering.
- HubSpot integration orchestration, customer portals and AI-enabled CRM extensions.
Research before choosing
- Relevant technical service capability. Confirm comparable production work, technical ownership and ongoing support.
- Confirm a comparable implementation reference and delivery team before selection.
- Broader integration capability; the cited source does not establish this exact connector implementation. Request an exact-platform client reference, architecture and support plan.
- Request a comparable client reference and confirm the delivery team
Source: Provider service offeringFacts from the company’s own website and public sources, checked 22 October 2026. Not a ranking.
How this shortlist was made: partners were assessed on category-specific evidence, based on public sources, mainly provider sources. Tier and category evidence are separate. A service page establishes a capability claim, not independently verified delivery quality. Team quality and comparable client references still need checking before selection. Reviewed 22 October 2026. The order is not a ranking. See How We Choose.
How to choose
- Ask for a reference with the same scope, and the same platform version where it applies.
- Confirm who will deliver the work and where they are based.
- Agree what is in scope: setup, integration, training and ongoing support.
- Check the partner's tier on HubSpot's own directory, then read the evidence link on its card.
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