Invoice Validation

Ensuring you are paying the correct charges for your utilities

1 in 11 utility invoices contains errors or discrepancies, leading to unnecessary costs and paying more than you need. ista's ISO9001:2008 accredited Invoice Validation service ensures you only pay what is owed.

How do we do it?

We validate each of your invoices against multiple criteria. Our bespoke istaNet platform will automatically assess each invoice, highlighting those that are outside the threshold. Our data team will then review each validation failure and determine the appropriate course of action. We always include a human check, which provides context and detail that an automated script cannot. We are continually enhancing our validation system, meaning if the market, regulations, or your requirements change, we have the ability to react and continue to provide our high-quality service.

What's the process?

Once your invoices have been reviewed, they will be assigned one of three statuses:

  • Approved - these invoices have passed validation and should be paid.
  • Approved, Query - These invoices have passed validation, however, ista has raised a query with the supplier. Dependent on the response and justification from the supplier, a credit may be received and processed.
  • Not approved - these invoices should not be paid, and ista will communicate with the supplier to obtain a credit note cancel;ing the invoice(s).


Transparent Billing: Pay Only What You Owe with Our Invoice Validation

  • Cost Savings: ista Invoice Validation provides a rapid return on investment, often resulting in savings that are multiple times the cost of service. With energy price risks1 in 11 utility invoices contains errors or discrepancies, leading to unnecessary costs and paying more than you need. ista’s ISO9001:2008 accredited Invoice Validation service ensures you only pay what is owed, removing incorrect charges is a simple way to ensure you are minimising your exposure to these increases.
  • Time Savings: Resolving invoicing issues with suppliers can take a significant amount of time and effort - time you could be spending on other areas of your business. Our dedicated team uses 25 years of expertise and cutting-edge technology to manage, assess and rectify issues with your utility invoices and payments.


Energy Accounting

Understand your full utility expenditure

ista provides you solutions to see and manage your full energy costs, carbon and consumption from one reporting platform. Our systems provides a flexibility to match your organisational hierarchy and to understand your utilities. This helps you to see the total picture and to drill down into each site and to each meter. We give you confidence and transparency in understanding how much your utilities cost, where and when you are using them and how you can save energy.

The advantage of using our solutions

  • Clear and better transparency in your energy costs, consumption and carbon usage
  • A single platform to collate, validate and report your companies energy bills
  • Pay for only what you use
  • Conformance and regulatory reporting from accurate data; minimising CRC and ESOS administration
  • Expert advice and guidance on energy for you across your company 

Energy Procurement

Are you a business that needs help with electricity, gas or water procurement?

The volatility of the markets and the growth of non-energy charges present businesses with a challenge: How to minimise cost.

ista currently manage over 1TW of gas and electricity contracts on behalf of a variety of clients. From single site SME’s to large multi-site retailers and industrial consumers, operating both fixed and flexible contracts; all contracts tailor-made to meet a clients specific needs. 

ista have both the expertise and systems to help you through the procurement process either as a standalone resource or to compliment your existing in-house facilities.

Your Benefits

  • Industry Knowledge – As a former supplier, ista has an in-depth understanding of industry communication 
  • Risk Analysis – Measure and quantify market drivers and associated risks
  • Independent advice – No allegiance to a single supplier and ista is account managed with all major energy suppliers
  • Purchasing expertise – Over 20 years experience
  • Constant market monitoring - ista do not follow the calendar and are proactive in approach. Procurement is treated as a continual process.
  • Effective communication – Providing analysis and recommendations in a meaningful way, ensuring you understand your role in the process and the decision points you need to make and why.

Smart Metering

Need to improve transparency in your energy use?

ista provides a complete range of utility metering and data collection solutions helping to put you back in control of your costs. Whether you require better transparency in you electricity, gas, water or heat usage we have a solution for you.

Typical services include:

  • Smart metering – Allows you to monitor energy consumption and implement changes to reduce costs.  
  • Sub metering for energy management cost centre allocation or tenant billing.
  • Procurement of best Meter Operator and Data Collector - for half Hourly (HH) supplies. This promotes best price and national service.
  • Data logging for other utilities or for efficiency studies of different plant on site. 

Smart Meter features

  • remote reading of MID and Ofgem approved meters via GSM and internet technologies
  • detailed profile data shows consumption for each day, drill down to a frequency of 1 minute where required
  • register reads are passed to your energy supplier for billing; so your invoices no longer have estimated readings
  • actual readings in your bills reduce administration costs and removes overcharges and errors
  • shadow invoices and accruals can be generated from the actual data in the time period that you require; i.e. 445 or weekly management accounting  
  • daily web access to meter readings and consumption reports
  • exception reports and energy analysis through ista online portals
  • the industry approved energy meters qualify for Enhanced Capital Allowance Scheme and can be offset against Corporation Tax

Sub Metering

If the level of detail provided by your main meter is insufficient for your requirements, consider sub metering - a cost-efficient solution to enable the metering of separate areas within a large building. Applications include tenant billing for parts of a building, specific energy management targets within the same site.

ista can advise on all aspects of sub metering from design, and project management to ongoing service provision.

Meter Operator and Data Collection

ista can advise on all aspects of meter operation, data collection and data aggregation services including sourcing national agreements, service specification and benchmarking of costs.

Electricity supplies over 100kW are required by law to have half hourly (HH) metering equipment that can be read remotely.  Appointing a 'Meter Operator' who supplies and maintains the metering system and communication link is the responsibility of the consumer. The UK market for meter operator services is highly competitive: many customers (particularly those with large portfolios) can achieve significant cost savings and service enhancement by sourcing a national meter operator agreement.

The opportunity for consumers to nominate their own Data Collector/Data Aggregator (DA/DC) has existed since 1998. Many customers have still not taken advantage of this, leaving their chosen supplier to appoint their preferred provider. There are significant advantages nominating your own DA/DC, including enhanced data, provision often at little or no extra cost.

Site Works

New utility infrastructure, upgrades, relocations and removals

Many of our clients experience significant problems installing, upgrading or removing utility infrastructure and ensuring a projects completion to meet target opening or handover dates. 

Delays can be costly. 

The process and industry relationship knowledge required when dealing with utilities can be complex and time consuming. 

ista has a dedicated team of technical engineers who can assist in fully managing this process for you. 

Your Benefits

  • A dedicated department proactively managing the entire multi-utility projects from concept to completion
  • Assistance with feasibility studies and provision of service location plans
  • Independent advice and the ability to present options on the competitive element of a project
  • Managing expectations to ensure deadlines are adhered to, providing both transparency and reliability
  • Co-ordination of all parties involved in a projects delivery
  • Contract negotiation ensuring you get the best Gas/Electricity/Metering contracts available.
  • Confidence – ista successfully deliver over 100 projects per annum

Contact us to find out more

The Officers' Mess
Royston Road
CB22 4QH

+44 (0) 1223 874 974